ArgumentOutOfRangeException Class

Reference

Definition

Namespace:: System

Assembly:: System.Runtime.dll

Assembly:: mscorlib.dll

Assembly:: netstandard.dll

Source:: ArgumentOutOfRangeException.cs

Source:: ArgumentOutOfRangeException.cs

Source:: ArgumentOutOfRangeException.cs

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

The exception that is thrown when the value of an argument is outside the allowable range of values as defined by the invoked method.

public ref class ArgumentOutOfRangeException : ArgumentException

public class ArgumentOutOfRangeException : ArgumentException

[System.Serializable]
public class ArgumentOutOfRangeException : ArgumentException

[System.Serializable]
[System.Runtime.InteropServices.ComVisible(true)]
public class ArgumentOutOfRangeException : ArgumentException

type ArgumentOutOfRangeException = class
    inherit ArgumentException

type ArgumentOutOfRangeException = class
    inherit ArgumentException
    interface ISerializable

[<System.Serializable>]
type ArgumentOutOfRangeException = class
    inherit ArgumentException
    interface ISerializable

[<System.Serializable>]
[<System.Runtime.InteropServices.ComVisible(true)>]
type ArgumentOutOfRangeException = class
    inherit ArgumentException
    interface ISerializable

Public Class ArgumentOutOfRangeException
Inherits ArgumentException

Inheritance: Object

Exception

ArgumentException
ArgumentOutOfRangeException

Inheritance: Object

Exception

SystemException

ArgumentException
ArgumentOutOfRangeException

Attributes: SerializableAttribute ComVisibleAttribute

Implements: ISerializable

Examples

The following example defines a class to contain information about an invited guest. If the guest is younger than 21, an ArgumentOutOfRangeException exception is thrown.

using System;
using static System.Console;

public class Program
{
    public static void Main(string[] args)
    {
        try
        {
            var guest1 = new Guest("Ben", "Miller", 17);
            WriteLine(guest1.GuestInfo);
        }
        catch (ArgumentOutOfRangeException argumentOutOfRangeException)
        {
            WriteLine($"Error: {argumentOutOfRangeException.Message}");
        }
    }
}

class Guest
{
    private const int minimumRequiredAge = 21;

    private string firstName;
    private string lastName;
    private int age;

    public Guest(string firstName, string lastName, int age)
    {
        if (age < minimumRequiredAge)
            throw new ArgumentOutOfRangeException(nameof(age), $"All guests must be {minimumRequiredAge}-years-old or older.");

        this.firstName = firstName;
        this.lastName = lastName;
        this.age = age;
    }

    public string GuestInfo => $"{firstName} {lastName}, {age}";
}

open System

type Guest(fName: string, lName: string, age: int) =
    let minimumRequiredAge = 21

    do if age < minimumRequiredAge then 
        raise (ArgumentOutOfRangeException(nameof age, $"All guests must be {minimumRequiredAge}-years-old or older."))

    member _.FirstName = fName
    member _.LastName = lName
    member _.GuestInfo() = $"{fName} {lName}, {age}"

try
    let guest1 = Guest("Ben", "Miller", 17);
    printfn $"{guest1.GuestInfo()}"
with
| :? ArgumentOutOfRangeException as e ->
    printfn $"Error: {e.Message}"

Module Module1
   Public Sub Main()
       Try
           Dim guest1 As Guest = New Guest("Ben", "Miller", 17)
           Console.WriteLine(guest1.GuestInfo)
       Catch outOfRange As ArgumentOutOfRangeException
           Console.WriteLine("Error: {0}", outOfRange.Message)
       End Try
   End Sub
End Module

Class Guest
    Private FirstName As String
    Private LastName As String
    Private Age As Integer

    Public Sub New(ByVal fName As String, ByVal lName As String, ByVal age As Integer)
        MyBase.New()
        FirstName = fName
        LastName = lName
        If (age < 21) Then
            Throw New ArgumentOutOfRangeException("age", "All guests must be 21-years-old or older.")
        Else
            age = age
        End If
    End Sub

    Public Function GuestInfo() As String
        Dim gInfo As String = (FirstName + (" " _
                    + (Me.LastName + (", " + Me.Age.ToString))))
        Return gInfo
    End Function
End Class

Remarks

An ArgumentOutOfRangeException exception is thrown when a method is invoked and at least one of the arguments passed to the method is not null and contains an invalid value that is not a member of the set of values expected for the argument. The ParamName property identifies the invalid argument, and the ActualValue property, if a value is present, identifies the invalid value.

Typically, an ArgumentOutOfRangeException results from developer error. Instead of handling the exception in a try/catch block, you should eliminate the cause of the exception or, if the argument is returned by a method call or input by the user before being passed to the method that throws the exception, you should validate arguments before passing them to the method.

ArgumentOutOfRangeException is used extensively by:

Classes in the System.Collections and System.IO namespaces.
The Array class.
String manipulation methods in the String class.

The conditions in which an ArgumentOutOfRangeException exception is thrown include the following:

You are retrieving the member of a collection by its index number, and the index number is invalid.

This is the most common cause of an ArgumentOutOfRangeException exception. Typically, the index number is invalid for one of four reasons:

The collection has no members, and your code assumes that it does. The following example attempts to retrieve the first element of a collection that has no elements:

using System;
using System.Collections.Generic;

public class Example4
{
   public static void Main()
   {
      var list = new List<string>();
      Console.WriteLine("Number of items: {0}", list.Count);
      try {
         Console.WriteLine("The first item: '{0}'", list[0]);
      }
      catch (ArgumentOutOfRangeException e) {
         Console.WriteLine(e.Message);
      }
   }
}
// The example displays the following output:
//   Number of items: 0
//   Index was out of range. Must be non-negative and less than the size of the collection.
//   Parameter name: index

open System


let list = ResizeArray<string>()
printfn $"Number of items: {list.Count}"
try
    printfn $"The first item: '{list[0]}'"
with 
| :? ArgumentOutOfRangeException as e ->
    printfn $"{e.Message}"

// The example displays the following output:
//   Number of items: 0
//   Index was out of range. Must be non-negative and less than the size of the collection. (Parameter 'index')

Imports System.Collections.Generic

Module Example
   Public Sub Main()
      Dim list As New List(Of String)
      Console.WriteLine("Number of items: {0}", list.Count)
      Try
         Console.WriteLine("The first item: '{0}'", list(0))
      Catch e As ArgumentOutOfRangeException
         Console.WriteLine(e.Message)
      End Try
   End Sub
End Module
' The example displays the following output:
'   Number of items: 0
'   Index was out of range. Must be non-negative and less than the size of the collection.
'   Parameter name: index

To prevent the exception, check whether the collection's Count property is greater than zero before attempting to retrieve any members, as the following code fragment does.

if (list.Count > 0)
   Console.WriteLine("The first item: '{0}'", list[0]);

if list.Count > 0 then
    printfn $"The first item: '{list[0]}'"

If list.Count > 0 Then
   Console.WriteLine("The first item: '{0}'", list(0))
End If

In some cases, the exception may occur because you are attempting to add a member to a collection by using an index that does not exist, rather than by calling the method, such as Add, that exists for this purpose. The following example attempts to add an element to a collection by using a non-existent index rather than calling the List<T>.Add method.

using System;
using System.Collections.Generic;

public class Example13
{
   public static void Main()
   {
      var numbers = new List<int>();
      numbers.AddRange( new int[] { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 20 } );

      var squares = new List<int>();
      for (int ctr = 0; ctr < numbers.Count; ctr++)
         squares[ctr] = (int) Math.Pow(numbers[ctr], 2);
   }
}
// The example displays the following output:
//    Unhandled Exception: System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection.
//    Parameter name: index
//       at System.ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument argument, ExceptionResource resource)
//       at Example.Main()

let numbers = ResizeArray<int>()
numbers.AddRange [ 0; 1; 2; 3; 4; 5; 6; 7; 8; 9; 20 ]

let squares = ResizeArray<int>()
for  ctr = 0 to numbers.Count - 1 do
    squares[ctr] <- int (float numbers[ctr] ** 2)

// The example displays the following output:
//    Unhandled Exception: System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection. (Parameter 'index')
//       at System.ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument argument, ExceptionResource resource)
//       at <StartupCode$argumentoutofrangeexception>.$NoElements.main@()

Imports System.Collections.Generic

Module Example
   Public Sub Main()
      Dim numbers As New List(Of Integer)
      numbers.AddRange( { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 20 } )
      
      Dim squares As New List(Of Integer)
      For ctr As Integer = 0 To numbers.Count - 1
         squares(ctr) = CInt(numbers(ctr) ^ 2) 
      Next
   End Sub
End Module
' The example displays the following output:
'    Unhandled Exception: System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection.
'    Parameter name: index
'       at System.ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument argument, ExceptionResource resource)
'       at Example.Main()

The following code fragment corrects this error:

var squares = new List<int>();
for (int ctr = 0; ctr < numbers.Count; ctr++)
   squares.Add((int) Math.Pow(numbers[ctr], 2));

let squares = ResizeArray<int>()
for ctr = 0 to numbers.Count - 1 do
    squares.Add(int (float numbers[ctr] ** 2))

Dim squares As New List(Of Integer)
For ctr As Integer = 0 To numbers.Count - 1
   squares.Add(CInt(numbers(ctr) ^ 2)) 
Next

You're attempting to retrieve an item whose index is negative. This usually occurs because you've searched a collection for the index of a particular element and have erroneously assumed that the search is successful. In the following example, the call to the List<T>.FindIndex(Predicate<T>) method fails to find a string equal to "Z" and so returns -1. However, this is an invalid index value.

using System;
using System.Collections.Generic;

public class Example
{
   public static void Main()
   {
      var list = new List<string>();
      list.AddRange( new String[] { "A", "B", "C" } );
      // Get the index of the element whose value is "Z".
      int index = list.FindIndex((new StringSearcher("Z")).FindEquals);
      try {
         Console.WriteLine("Index {0} contains '{1}'", index, list[index]);
      }
      catch (ArgumentOutOfRangeException e) {
         Console.WriteLine(e.Message);
      }
   }
}

internal class StringSearcher
{
   string value;

   public StringSearcher(string value)
   {
      this.value = value;
   }

   public bool FindEquals(string s)
   {
      return s.Equals(value, StringComparison.InvariantCulture);
   }
}
// The example displays the following output:
//   Index was out of range. Must be non-negative and less than the size of the collection.
//   Parameter name: index

open System

module StringSearcher =
    let findEquals (s: string) value =
        s.Equals(value, StringComparison.InvariantCulture)

let list = ResizeArray<string>()
list.AddRange [ "A"; "B"; "C" ]
// Get the index of the element whose value is "Z".
let index = list.FindIndex(StringSearcher.findEquals "Z")
try 
    printfn $"Index {index} contains '{list[index]}'"
with 
| :? ArgumentOutOfRangeException as e ->
    printfn $"{e.Message}" 

// The example displays the following output:
//   Index was out of range. Must be non-negative and less than the size of the collection. (Parameter 'index')

Imports System.Collections.Generic

Module Example
   Public Sub Main()
      Dim list As New List(Of String) 
      list.AddRange( { "A", "B", "C" } )
      ' Get the index of the element whose value is "Z".
      Dim index As Integer = list.FindIndex(AddressOf (New StringSearcher("Z")).FindEquals)
      Try
         Console.WriteLine("Index {0} contains '{1}'", index, list(index)) 
      Catch e As ArgumentOutOfRangeException
         Console.WriteLine(e.Message)
      End Try
   End Sub
End Module

Friend Class StringSearcher
   Dim value As String
   
   Public Sub New(value As String)
      Me.value = value
   End Sub
   
   Public Function FindEquals(s As String) As Boolean
      Return s.Equals(value, StringComparison.InvariantCulture) 
   End Function
End Class
' The example displays the following output:
'   Index was out of range. Must be non-negative and less than the size of the collection.
'   Parameter name: index

To prevent the exception, check that the search is successful by making sure that the returned index is greater than or equal to zero before attempting to retrieve the item from the collection, as the following code fragment does.

// Get the index of the element whose value is "Z".
int index = list.FindIndex((new StringSearcher("Z")).FindEquals);
if (index >= 0)
   Console.WriteLine("'Z' is found at index {0}", list[index]);

// Get the index of the element whose value is "Z".
let index = list.FindIndex(StringSearcher.findEquals "Z")
if index >= 0 then
    printfn $"'Z' is found at index {list[index]}"

' Get the index of the element whose value is "Z".
Dim index As Integer = list.FindIndex(AddressOf (New StringSearcher("Z")).FindEquals)
If index >= 0 Then
   Console.WriteLine("Index {0} contains '{1}'", index, list(index)) 
End If

You're attempting to retrieve an element whose index is equal to the value of the collection's Count property, as the following example illustrates.

using System;
using System.Collections.Generic;

public class Example8
{
   public static void Main()
   {
      var list = new List<string>();
      list.AddRange( new String[] { "A", "B", "C" } );
      try {
         // Display the elements in the list by index.
         for (int ctr = 0; ctr <= list.Count; ctr++)
            Console.WriteLine("Index {0}: {1}", ctr, list[ctr]);
      }
      catch (ArgumentOutOfRangeException e) {
         Console.WriteLine(e.Message);
      }
   }
}
// The example displays the following output:
//   Index 0: A
//   Index 1: B
//   Index 2: C
//   Index was out of range. Must be non-negative and less than the size of the collection.
//   Parameter name: index

open System

let list = ResizeArray<string>()
list.AddRange [ "A"; "B"; "C" ] 
try
    // Display the elements in the list by index.
    for i = 0 to list.Count do
        printfn $"Index {i}: {list[i]}"
with 
| :? ArgumentOutOfRangeException as e ->
    printfn $"{e.Message}" 
      
// The example displays the following output:
//   Index 0: A
//   Index 1: B
//   Index 2: C
//   Index was out of range. Must be non-negative and less than the size of the collection. (Parameter 'index')

Imports System.Collections.Generic

Module Example
   Public Sub Main()
      Dim list As New List(Of String) 
      list.AddRange( { "A", "B", "C" } )
      Try
         ' Display the elements in the list by index.
         For ctr As Integer = 0 To list.Count
            Console.WriteLine("Index {0}: {1}", ctr, list(ctr)) 
         Next   
      Catch e As ArgumentOutOfRangeException
         Console.WriteLine(e.Message)
      End Try
   End Sub
End Module
' The example displays the following output:
'   Index 0: A
'   Index 1: B
'   Index 2: C
'   Index was out of range. Must be non-negative and less than the size of the collection.
'   Parameter name: index

Because collections in .NET use zero-based indexing, the first element of the collection is at index 0, and the last element is at index Count - 1. You can eliminate the error by ensuring that you access the last element at index Count - 1, as the following code does.

// Display the elements in the list by index.
for (int ctr = 0; ctr < list.Count; ctr++)
   Console.WriteLine("Index {0}: {1}", ctr, list[ctr]);

// Display the elements in the list by index.
for i = 0 to list.Count - 1 do
    printfn $"Index {i}: {list[i]}"

' Display the elements in the list by index.
For ctr As Integer = 0 To list.Count - 1 
   Console.WriteLine("Index {0}: {1}", ctr, list(ctr)) 
Next

You are attempting to perform a string operation by calling a string manipulation method, and the starting index does not exist in the string.

Overloads of methods such as such as String.Compare, String.CompareOrdinal, String.IndexOf, IndexOfAny, String.Insert, String.LastIndexOf, String.LastIndexOfAny, Remove, or String.Substring that allow you to specify the starting index of the operation require that the index be a valid position within the string. Valid indexes range from 0 to String.Length - 1.

There are four common causes of this ArgumentOutOfRangeException exception:

You are working with an empty string, or String.Empty. Because its String.Length property returns 0, any attempt to manipulate it by index throws an ArgumentOutOfRangeException exception. The following example, defines a GetFirstCharacter method that returns the first character of a string. If the string is empty, as the final string passed to the method is, the method throws an ArgumentOutOfRangeException exception.

using System;

public class Example1
{
    public static void Main()
    {
        String[] words = { "the", "today", "tomorrow", " ", "" };
        foreach (var word in words)
            Console.WriteLine("First character of '{0}': '{1}'",
                              word, GetFirstCharacter(word));
    }

    private static char GetFirstCharacter(string s)
    {
        return s[0];
    }
}
// The example displays the following output:
//    First character of //the//: //t//
//    First character of //today//: //t//
//    First character of //tomorrow//: //t//
//    First character of // //: // //
//
//    Unhandled Exception: System.IndexOutOfRangeException: Index was outside the bounds of the array.
//       at Example.Main()

open System

let getFirstCharacter (s: string) = s[0]

let words = [ "the"; "today"; "tomorrow"; " "; "" ]
for word in words do
    printfn $"First character of '{word}': '{getFirstCharacter word}'"

// The example displays the following output:
//    First character of 'the': 't'
//    First character of 'today': 't'
//    First character of 'tomorrow': 't'
//    First character of ' ': ' '
//
//    Unhandled Exception: System.IndexOutOfRangeException: Index was outside the bounds of the array.
//       at <StartupCode$argumentoutofrangeexception>.$EmptyString1.main@()

Module Example
   Public Sub Main()
       Dim words() As String = { "the", "today", "tomorrow", " ", "" }
       For Each word In words
          Console.WriteLine("First character of '{0}': '{1}'", 
                            word, GetFirstCharacter(word))
       Next                     
   End Sub
   
   Private Function GetFirstCharacter(s As String) As Char
      Return s(0)
   End Function
End Module
' The example displays the following output:
'    First character of 'the': 't'
'    First character of 'today': 't'
'    First character of 'tomorrow': 't'
'    First character of ' ': ' '
'    
'    Unhandled Exception: System.IndexOutOfRangeException: Index was outside the bounds of the array.
'       at Example.Main()

You can eliminate the exception by testing whether the string's String.Length is greater than zero or by calling the IsNullOrEmpty method to ensure that the string is not null or empty. The following code fragment does the latter. In this case, if the string is null or empty, the GetFirstCharacter method returns U+0000.

static char GetFirstCharacter(string s)
{
    if (string.IsNullOrEmpty(s))
        return '\u0000';
    else
        return s[0];
}

let getFirstCharacter (s: string) =
   if String.IsNullOrEmpty s then
      '\u0000'
   else
      s[0]

Function GetFirstCharacter(s As String) As Char
   If String.IsNullOrEmpty(s) Then 
      Return ChrW(0)
   Else   
      Return s(0)
   End If   
End Function

You're manipulating a string based on the position of a substring within that string, and you've failed to determine whether the substring was actually found.

The following example extracts the second word of a two-word phrase. It throws an ArgumentOutOfRangeException exception if the phrase consists of only one word, and therefore does not contain an embedded space character. This occurs because the call to the String.IndexOf(String) method returns -1 to indicate that the search failed, and this invalid value is then passed to the String.Substring(Int32) method.

using System;

public class Example17
{
   public static void Main()
   {
      String[] phrases = { "ocean blue", "concerned citizen",
                           "runOnPhrase" };
      foreach (var phrase in phrases)
         Console.WriteLine("Second word is {0}", GetSecondWord(phrase));
   }

   static string GetSecondWord(string s)
   {
      int pos = s.IndexOf(" ");
      return s.Substring(pos).Trim();
   }
}
// The example displays the following output:
//    Second word is blue
//    Second word is citizen
//
//    Unhandled Exception: System.ArgumentOutOfRangeException: StartIndex cannot be less than zero.
//    Parameter name: startIndex
//       at System.String.Substring(Int32 startIndex, Int32 length)
//       at Example17.GetSecondWord(String s)
//       at Example17.Main()

let getSecondWord (s: string) =
    let pos = s.IndexOf " "
    s.Substring(pos).Trim()

let phrases = [ "ocean blue"; "concerned citizen"; "runOnPhrase" ]
for phrase in phrases do
    printfn $"Second word is {getSecondWord phrase}"

// The example displays the following output:
//    Second word is blue
//    Second word is citizen
//
//    Unhandled Exception: System.ArgumentOutOfRangeException: StartIndex cannot be less than zero. (Parameter 'startIndex')
//       at System.String.Substring(Int32 startIndex, Int32 length)
//       at System.String.Substring(Int32 startIndex)
//       at NoFind1.getSecondWord(String s)
//       at <StartupCode$argumentoutofrangeexception>.$NoFind1.main@()

Module Example
   Public Sub Main()
      Dim phrases() As String = { "ocean blue", "concerned citizen", 
                                  "runOnPhrase" }
      For Each phrase In phrases
         Console.WriteLine("Second word is {0}", GetSecondWord(phrase))
      Next                            
  End Sub
  
  Function GetSecondWord(s As String) As String
     Dim pos As Integer = s.IndexOf(" ")
     Return s.Substring(pos).Trim()
  End Function
End Module
' The example displays the following output:
'       Second word is blue
'       Second word is citizen
'       
'       Unhandled Exception: System.ArgumentOutOfRangeException: StartIndex cannot be less than zero.
'       Parameter name: startIndex
'          at System.String.Substring(Int32 startIndex, Int32 length)
'          at Example.GetSecondWord(String s)
'          at Example.Main()

To eliminate the exception, validate the value returned by the string search method before calling the string manipulation method.

using System;

public class Example18
{
   public static void Main()
   {
      String[] phrases = { "ocean blue", "concerned citizen",
                           "runOnPhrase" };
      foreach (var phrase in phrases) {
         string word = GetSecondWord(phrase);
         if (! string.IsNullOrEmpty(word))
            Console.WriteLine("Second word is {0}", word);
      }
   }

   static string GetSecondWord(string s)
   {
      int pos = s.IndexOf(" ");
      if (pos >= 0)
         return s.Substring(pos).Trim();
      else
         return string.Empty;
   }
}
// The example displays the following output:
//       Second word is blue
//       Second word is citizen

open System

let getSecondWord (s: string) =
    let pos = s.IndexOf " "
    if pos >= 0 then
        s.Substring(pos).Trim()
    else 
        String.Empty

let phrases = [ "ocean blue"; "concerned citizen"; "runOnPhrase" ]
for phrase in phrases do
    let word = getSecondWord phrase
    if not (String.IsNullOrEmpty word) then
        printfn $"Second word is {word}"

// The example displays the following output:
//       Second word is blue
//       Second word is citizen

Module Example
   Public Sub Main()
      Dim phrases() As String = { "ocean blue", "concerned citizen", 
                                  "runOnPhrase" }
      For Each phrase In phrases
         Dim word As String = GetSecondWord(phrase)
         If Not String.IsNullOrEmpty(word) Then _
            Console.WriteLine("Second word is {0}", word)
      Next                            
   End Sub
  
   Function GetSecondWord(s As String) As String
      Dim pos As Integer = s.IndexOf(" ")
      If pos >= 0
          Return s.Substring(pos).Trim()
      Else
         Return String.Empty
      End If
  End Function
End Module
' The example displays the following output:
'       Second word is blue
'       Second word is citizen

You've attempted to extract a substring that is outside the range of the current string.

The methods that extract substrings all require that you specify the starting position of the substring and, for substrings that do not continue to the end of the string, the number of characters in the substring. Note that this is not the index of the last character in the substring.

An ArgumentOutOfRangeException exception is typically thrown in this case because you've incorrectly calculated the number of characters in the substring. If you are using a search method like String.IndexOf to identify the starting and ending positions of a substring:

If the character in the ending position returned by String.IndexOf is to be included in the substring, the ending position of the substring is given by the formula
```
endIndex - startIndex + 1
```

If the character in the ending position returned by String.IndexOf is to be excluded from the substring, the ending position of the substring is given by the formula

endIndex - startIndex

The following example defines a FindWords method that uses the String.IndexOfAny(Char[], Int32) method to identify space characters and punctuation marks in a string and returns an array that contains the words found in the string.

using System;
using System.Collections.Generic;

public class Example19
{
   public static void Main()
   {
      string sentence = "This is a simple, short sentence.";
      Console.WriteLine("Words in '{0}':", sentence);
      foreach (var word in FindWords(sentence))
         Console.WriteLine("   '{0}'", word);
   }

   static String[] FindWords(string s)
   {
      int start = 0, end = 0;
      Char[] delimiters = { ' ', '.', ',', ';', ':', '(', ')' };
      var words = new List<string>();

      while (end >= 0) {
         end = s.IndexOfAny(delimiters, start);
         if (end >= 0) {
            if (end - start > 0)
               words.Add(s.Substring(start, end - start));

            start = end + 1;
         }
         else {
            if (start < s.Length - 1)
               words.Add(s.Substring(start));
         }
      }
      return words.ToArray();
   }
}
// The example displays the following output:
//       Words in 'This is a simple, short sentence.':
//          'This'
//          'is'
//          'a'
//          'simple'
//          'short'
//          'sentence'


let findWords (s: string) =
    let mutable start, end' = 0, 0
    let delimiters = [| ' '; '.'; ','; ';'; ':'; '('; ')' |]
    let words = ResizeArray<string>()
    while end' >= 0 do
        end' <- s.IndexOfAny(delimiters, start)
        if end' >= 0 then
            if end' - start > 0 then
                words.Add(s.Substring(start, end' - start))
            start <- end' + 1
        elif start < s.Length - 1 then
            words.Add(s.Substring start)
    words.ToArray()

let sentence = "This is a simple, short sentence."
printfn $"Words in '{sentence}':"
for word in findWords sentence do
    printfn $"   '{word}'"

// The example displays the following output:
//       Words in 'This is a simple, short sentence.':
//          'This'
//          'is'
//          'a'
//          'simple'
//          'short'
//          'sentence'

Imports System.Collections.Generic

Module Example
   Public Sub Main()
      Dim sentence As String = "This is a simple, short sentence."
      Console.WriteLine("Words in '{0}':", sentence)
      For Each word In FindWords(sentence)
         Console.WriteLine("   '{0}'", word)
      Next
   End Sub
   
   Function FindWords(s As String) As String()
      Dim start, ending As Integer
      Dim delimiters() As Char = { " "c, "."c, ","c, ";"c, ":"c,
                                   "("c, ")"c }
      Dim words As New List(Of String)()

      Do While ending >= 0
         ending = s.IndexOfAny(delimiters, start)
         If ending >= 0
            If ending - start > 0 Then
               words.Add(s.Substring(start, ending - start)) 
            End If
            start = ending + 1
         Else
            If start < s.Length - 1 Then
               words.Add(s.Substring(start))
            End If      
         End If
      Loop    
      Return words.ToArray()                         
   End Function
End Module
' The example displays the following output:
'       Words in 'This is a simple, short sentence.':
'          'This'
'          'is'
'          'a'
'          'simple'
'          'short'
'          'sentence'

You have passed a negative number to a method with an argument that requires only positive numbers and zero, or you have passed either a negative number or zero to a method with an argument that requires only positive numbers.

For example, the Array.CreateInstance(Type, Int32, Int32, Int32) method requires that you specify the number of elements in each dimension of a two-dimensional array; valid values for each dimension can range from 0 to Int32.MaxValue. But because the dimension argument in the following example has a negative value, the method throws an ArgumentOutOfRangeException exception.

using System;

public class Example01
{
    public static void Main()
    {
        int dimension1 = 10;
        int dimension2 = -1;
        try
        {
            Array arr = Array.CreateInstance(typeof(string),
                                             dimension1, dimension2);
        }
        catch (ArgumentOutOfRangeException e)
        {
            if (e.ActualValue != null)
                Console.WriteLine("{0} is an invalid value for {1}: ", e.ActualValue, e.ParamName);
            Console.WriteLine(e.Message);
        }
    }
}
// The example displays the following output:
//     Non-negative number required.
//     Parameter name: length2

open System

let dimension1 = 10
let dimension2 = -1
try
    let arr = Array.CreateInstance(typeof<string>, dimension1, dimension2)
    printfn "%A" arr
with 
| :? ArgumentOutOfRangeException as e ->
    if not (isNull e.ActualValue) then
        printfn $"{e.ActualValue} is an invalid value for {e.ParamName}: "
    printfn $"{e.Message}"

// The example displays the following output:
//     Non-negative number required. (Parameter 'length2')

Module Example
   Public Sub Main()
      Dim dimension1 As Integer = 10
      Dim dimension2 As Integer = -1
      Try
         Dim arr AS Array = Array.CreateInstance(GetType(String), 
                                                 dimension1, dimension2)
      Catch e As ArgumentOutOfRangeException
         If e.ActualValue IsNot Nothing Then
            Console.WriteLine("{0} is an invalid value for {1}: ", 
                              e.ActualValue, e.ParamName)
         End If                     
         Console.WriteLine(e.Message)
      End Try
   End Sub
End Module
' The example displays the following output:
'     Non-negative number required.
'     Parameter name: length2

To correct the error, ensure that the value of the invalid argument is non-negative. You can do this by providing a valid value, as the following code fragment does.

int dimension1 = 10;
int dimension2 = 10;
Array arr = Array.CreateInstance(typeof(string),
                                 dimension1, dimension2);

let dimension1 = 10
let dimension2 = 10
let arr = Array.CreateInstance(typeof<string>, dimension1, dimension2)
printfn "%A" arr

Dim dimension1 As Integer = 10
Dim dimension2 As Integer = 10
Dim arr As Array = Array.CreateInstance(GetType(String), 
                                        dimension1, dimension2)

You can also validate the input and, if it is invalid, take some action. The following code fragment displays an error message instead of calling the method.

if (dimension1 < 0 || dimension2 < 0)
{
    Console.WriteLine("Unable to create the array.");
    Console.WriteLine("Specify non-negative values for the two dimensions.");
}
else
{
    arr = Array.CreateInstance(typeof(string),
                               dimension1, dimension2);
}

if dimension1 < 0 || dimension2 < 0 then
    printfn "Unable to create the array."
    printfn "Specify non-negative values for the two dimensions."
else
    let arr = Array.CreateInstance(typeof<string>, dimension1, dimension2)
    printfn "%A" arr

If dimension1 < 0 OrElse dimension2 < 0 Then
   Console.WriteLine("Unable to create the array.")
   Console.WriteLine("Specify non-negative values for the two dimensions.")
Else
   arr = Array.CreateInstance(GetType(String), 
                              dimension1, dimension2)   
End If

A race condition exists in an app that is multithreaded or has tasks that execute asynchronously and that updates an array or collection.

The following example uses a List<T> object to populate a collection of Continent objects. It throws an ArgumentOutOfRangeException if the example attempts to display the seven items in the collection before the collection is fully populated.

using System;
using System.Collections.Generic;
using System.Threading;

public class Continent
{
   public string? Name { get; set; }
   public int Population { get; set; }
   public Decimal Area { get; set; }
}

public class Example11
{
   static List<Continent> continents = new List<Continent>();
   static string? s_msg;

   public static void Main()
   {
      String[] names = { "Africa", "Antarctica", "Asia",
                         "Australia", "Europe", "North America",
                         "South America" };
      // Populate the list.
      foreach (var name in names) {
         var th = new Thread(PopulateContinents);
         th.Start(name);
      }
      Console.WriteLine(s_msg);
      Console.WriteLine();

      // Display the list.
      for (int ctr = 0; ctr < names.Length; ctr++) {
         var continent = continents[ctr];
         Console.WriteLine("{0}: Area: {1}, Population {2}",
                           continent.Name, continent.Population,
                           continent.Area);
      }
   }

   private static void PopulateContinents(Object? obj)
   {
      string? name = obj?.ToString();
      s_msg += string.Format("Adding '{0}' to the list.\n", name);
      var continent = new Continent();
      continent.Name = name;
      // Sleep to simulate retrieving remaining data.
      Thread.Sleep(50);
      continents.Add(continent);
   }
}
// The example displays output like the following:
//    Adding //Africa// to the list.
//    Adding //Antarctica// to the list.
//    Adding //Asia// to the list.
//    Adding //Australia// to the list.
//    Adding //Europe// to the list.
//    Adding //North America// to the list.
//    Adding //South America// to the list.
//
//
//
//    Unhandled Exception: System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection.
//    Parameter name: index
//       at System.ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument argument, ExceptionResource resource)
//       at Example.Main()

open System.Threading

type Continent =
    { Name: string
      Population: int
      Area: decimal }

let continents = ResizeArray<Continent>()
let mutable msg = ""

let names = 
    [ "Africa"; "Antarctica"; "Asia"
      "Australia"; "Europe"; "North America"
      "South America" ]

let populateContinents obj = 
    let name = string obj
    msg <- msg + $"Adding '{name}' to the list.\n"
    // Sleep to simulate retrieving data.
    Thread.Sleep 50
    let continent = 
        { Name = name
          Population = 0
          Area = 0M }
    continents.Add continent
      
// Populate the list.
for name in names do
    let th = Thread(ParameterizedThreadStart populateContinents)
    th.Start name
      
printfn $"{msg}\n"

// Display the list.
for i = 0 to names.Length - 1 do
    let continent = continents[i]
    printfn $"{continent.Name}: Area: {continent.Population}, Population {continent.Area}"

// The example displays output like the following:
//    Unhandled Exception: System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection. (Parameter 'index')
//       at System.Collections.Generic.List`1.get_Item(Int32 index)
//       at <StartupCode$argumentoutofrangeexception>.$Race1.main@()

Imports System.Collections.Generic
Imports System.Threading

Public Class Continent
   Public Property Name As String
   Public Property Population As Integer
   Public Property Area As Decimal  
End Class

Module Example
   Dim continents As New List(Of Continent)
   Dim msg As String 
      
   Public Sub Main()
      Dim names() As String = { "Africa", "Antarctica", "Asia", 
                                     "Australia", "Europe", "North America",
                                     "South America" }
      ' Populate the list.
      For Each name In names
         Dim th As New Thread(AddressOf PopulateContinents)
         th.Start(name)
      Next              
      Console.WriteLine(msg)
      Console.WriteLine()

      ' Display the list.
      For ctr As Integer = 0 To names.Length - 1
         Dim continent = continents(ctr)
         Console.WriteLine("{0}: Area: {1}, Population {2}", 
                           continent.Name, continent.Population,
                           continent.Area)
      Next
   End Sub
   
   Private Sub PopulateContinents(obj As Object)
      Dim name As String = obj.ToString()
      msg += String.Format("Adding '{0}' to the list.{1}", name, vbCrLf)
      Dim continent As New Continent()
      continent.Name = name
      ' Sleep to simulate retrieving remaining data.
      Thread.Sleep(50)
      continents.Add(continent)
   End Sub
End Module
' The example displays output like the following:
'    Adding 'Africa' to the list.
'    Adding 'Antarctica' to the list.
'    Adding 'Asia' to the list.
'    Adding 'Australia' to the list.
'    Adding 'Europe' to the list.
'    Adding 'North America' to the list.
'    Adding 'South America' to the list.
'    
'    
'    
'    Unhandled Exception: System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection.
'    Parameter name: index
'       at System.ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument argument, ExceptionResource resource)
'       at Example.Main()

In this case, two resources are accessed from multiple threads:

The continents collection. Its List<T>.Add method is called from multiple threads. In addition, the main or primary thread assumes the collection is fully populated with seven elements when it iterates its members.
The msg string, which is concatenated from multiple threads.

To correct the error, ensure that shared state is accessed in a thread-safe way, as follows.

if your app uses an array or collection object, consider using a thread-safe collection class, such as the types in the System.Collections.Concurrent namespace or the System.Collections.Immutable out-of-band release.
Ensure that shared state (that is, resources that can be accessed by multiple threads) is accessed in a thread-safe way, so that only one thread at a time has exclusive access to the resources. A large number of classes, such as CountdownEvent, Interlocked, Monitor, and Mutex, are available to synchronize access to resources. For more information, see Threading. In addition, language support is available through the lock statement in C# and the SyncLock construct in Visual Basic.

The following example addresses the ArgumentOutOfRangeException and the other issues from the previous example. It replaces the List<T> object with a ConcurrentBag<T> object to ensure that access to the collection is thread-safe, uses a CountdownEvent object to ensure that the application thread continues only after other threads have executed, and uses a lock to ensure that only one thread can access the msg variable at a time.

using System;
using System.Collections.Concurrent;
using System.Threading;

public class ContinentD
{
   public string? Name { get; set; }
   public int Population { get; set; }
   public Decimal Area { get; set; }
}

public class Example12
{
   static ConcurrentBag<ContinentD> ContinentDs = new ConcurrentBag<ContinentD>();
   static CountdownEvent? gate;
   static string msg = string.Empty;

   public static void Main()
   {
      String[] names = { "Africa", "Antarctica", "Asia",
                         "Australia", "Europe", "North America",
                         "South America" };
      gate = new CountdownEvent(names.Length);

      // Populate the list.
      foreach (var name in names) {
         var th = new Thread(PopulateContinentDs);
         th.Start(name);
      }

      // Display the list.
      gate.Wait();
      Console.WriteLine(msg);
      Console.WriteLine();

      var arr = ContinentDs.ToArray();
      for (int ctr = 0; ctr < names.Length; ctr++) {
         var ContinentD = arr[ctr];
         Console.WriteLine("{0}: Area: {1}, Population {2}",
                           ContinentD.Name, ContinentD.Population,
                           ContinentD.Area);
      }
   }

   private static void PopulateContinentDs(Object? obj)
   {
      string? name = obj?.ToString();
      lock(msg) {
         msg += string.Format("Adding '{0}' to the list.\n", name);
      }
      var ContinentD = new ContinentD();
      ContinentD.Name = name;
      // Sleep to simulate retrieving remaining data.
      Thread.Sleep(25);
      ContinentDs.Add(ContinentD);
      gate?.Signal();
   }
}
// The example displays output like the following:
//       Adding 'Africa' to the list.
//       Adding 'Antarctica' to the list.
//       Adding 'Asia' to the list.
//       Adding 'Australia' to the list.
//       Adding 'Europe' to the list.
//       Adding 'North America' to the list.
//       Adding 'South America' to the list.
//
//
//       Africa: Area: 0, Population 0
//       Antarctica: Area: 0, Population 0
//       Asia: Area: 0, Population 0
//       Australia: Area: 0, Population 0
//       Europe: Area: 0, Population 0
//       North America: Area: 0, Population 0
//       South America: Area: 0, Population 0

open System.Collections.Concurrent
open System.Threading

type Continent =
    { Name: string
      Population: int
      Area: decimal }

let continents = ConcurrentBag<Continent>();
let mutable msg = ""

let names = 
    [ "Africa"; "Antarctica"; "Asia"
      "Australia"; "Europe"; "North America"
      "South America" ]

let gate = new CountdownEvent(names.Length)

let populateContinents obj = 
    let name = string obj
    lock msg (fun () -> 
        msg <- msg + $"Adding '{name}' to the list.\n" )

    // Sleep to simulate retrieving remaining data.
    let continent = 
        { Name = name
          Population = 0
          Area = 0M }
    Thread.Sleep 25
    continents.Add continent
    gate.Signal() |> ignore

// Populate the list.
for name in names do
    let th = Thread(ParameterizedThreadStart populateContinents)
    th.Start name

// Display the list.
gate.Wait();
printfn $"{msg}\n"

let arr = continents.ToArray();
for i = 0 to names.Length - 1 do
    let continent = arr[i]
    printfn $"{continent.Name}: Area: {continent.Population}, Population {continent.Area}"

// The example displays output like the following:
//       Adding 'Africa' to the list.
//       Adding 'Antarctica' to the list.
//       Adding 'Asia' to the list.
//       Adding 'Australia' to the list.
//       Adding 'Europe' to the list.
//       Adding 'North America' to the list.
//       Adding 'South America' to the list.
//
//
//       Africa: Area: 0, Population 0
//       Antarctica: Area: 0, Population 0
//       Asia: Area: 0, Population 0
//       Australia: Area: 0, Population 0
//       Europe: Area: 0, Population 0
//       North America: Area: 0, Population 0
//       South America: Area: 0, Population 0

Imports System.Collections.Concurrent
Imports System.Threading

Public Class Continent
   Public Property Name As String
   Public Property Population As Integer
   Public Property Area As Decimal  
End Class

Module Example
   Dim continents As New ConcurrentBag(Of Continent)
   Dim gate As CountdownEvent
   Dim msg As String = String.Empty
      
   Public Sub Main()
      Dim names() As String = { "Africa", "Antarctica", "Asia", 
                                "Australia", "Europe", "North America",
                                "South America" }
      gate = new CountdownEvent(names.Length)
      
      ' Populate the list.
      For Each name In names
         Dim th As New Thread(AddressOf PopulateContinents)
         th.Start(name)
      Next              

      ' Display the list.
      gate.Wait()
      Console.WriteLine(msg)
      Console.WriteLine()

      For ctr As Integer = 0 To names.Length - 1
         Dim continent = continents(ctr)
         Console.WriteLine("{0}: Area: {1}, Population {2}", 
                           continent.Name, continent.Population,
                           continent.Area)
      Next
   End Sub
   
   Private Sub PopulateContinents(obj As Object)
      Dim name As String = obj.ToString()
      SyncLock msg 
         msg += String.Format("Adding '{0}' to the list.{1}", name, vbCrLf)
      End SyncLock
      Dim continent As New Continent()
      continent.Name = name
      ' Sleep to simulate retrieving remaining data.
      Thread.Sleep(25)
      continents.Add(continent)
      gate.Signal()
   End Sub
End Module
' The example displays output like the following:
'    Adding 'Africa' to the list.
'    Adding 'Antarctica' to the list.
'    Adding 'Asia' to the list.
'    Adding 'Australia' to the list.
'    Adding 'Europe' to the list.
'    Adding 'North America' to the list.
'    Adding 'South America' to the list.
'    
'    
'    Africa: Area: 0, Population 0
'    Antarctica: Area: 0, Population 0
'    Asia: Area: 0, Population 0
'    Australia: Area: 0, Population 0
'    Europe: Area: 0, Population 0
'    North America: Area: 0, Population 0
'    South America: Area: 0, Population 0

ArgumentOutOfRangeException uses the HRESULT COR_E_ARGUMENTOUTOFRANGE, which has the value 0x80131502.

For a list of initial property values for an instance of ArgumentOutOfRangeException, see the ArgumentOutOfRangeException constructors.

Constructors

ArgumentOutOfRangeException()	Initializes a new instance of the ArgumentOutOfRangeException class.
ArgumentOutOfRangeException(SerializationInfo, StreamingContext)	Obsolete. Initializes a new instance of the ArgumentOutOfRangeException class with serialized data.
ArgumentOutOfRangeException(String, Exception)	Initializes a new instance of the ArgumentOutOfRangeException class with a specified error message and the exception that is the cause of this exception.
ArgumentOutOfRangeException(String, Object, String)	Initializes a new instance of the ArgumentOutOfRangeException class with the parameter name, the value of the argument, and a specified error message.
ArgumentOutOfRangeException(String, String)	Initializes a new instance of the ArgumentOutOfRangeException class with the name of the parameter that causes this exception and a specified error message.
ArgumentOutOfRangeException(String)	Initializes a new instance of the ArgumentOutOfRangeException class with the name of the parameter that causes this exception.

Properties

ActualValue	Gets the argument value that causes this exception.
Data	Gets a collection of key/value pairs that provide additional user-defined information about the exception. (Inherited from Exception)
HelpLink	Gets or sets a link to the help file associated with this exception. (Inherited from Exception)
HResult	Gets or sets HRESULT, a coded numerical value that is assigned to a specific exception. (Inherited from Exception)
InnerException	Gets the Exception instance that caused the current exception. (Inherited from Exception)
Message	Gets the error message and the string representation of the invalid argument value, or only the error message if the argument value is null.
ParamName	Gets the name of the parameter that causes this exception. (Inherited from ArgumentException)
Source	Gets or sets the name of the application or the object that causes the error. (Inherited from Exception)
StackTrace	Gets a string representation of the immediate frames on the call stack. (Inherited from Exception)
TargetSite	Gets the method that throws the current exception. (Inherited from Exception)

Methods

Equals(Object)	Determines whether the specified object is equal to the current object. (Inherited from Object)
GetBaseException()	When overridden in a derived class, returns the Exception that is the root cause of one or more subsequent exceptions. (Inherited from Exception)
GetHashCode()	Serves as the default hash function. (Inherited from Object)
GetObjectData(SerializationInfo, StreamingContext)	Obsolete. Sets the SerializationInfo object with the invalid argument value and additional exception information.
GetObjectData(SerializationInfo, StreamingContext)	Obsolete. Sets the SerializationInfo object with the parameter name and additional exception information. (Inherited from ArgumentException)
GetType()	Gets the runtime type of the current instance. (Inherited from Exception)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
ThrowIfEqual<T>(T, T, String)	Throws an ArgumentOutOfRangeException if `value` is equal to `other`.
ThrowIfGreaterThan<T>(T, T, String)	Throws an ArgumentOutOfRangeException if `value` is greater than `other`.
ThrowIfGreaterThanOrEqual<T>(T, T, String)	Throws an ArgumentOutOfRangeException if `value` is greater than or equal to `other`.
ThrowIfLessThan<T>(T, T, String)	Throws an ArgumentOutOfRangeException if `value` is less than `other`.
ThrowIfLessThanOrEqual<T>(T, T, String)	Throws an ArgumentOutOfRangeException if `value` is less than or equal to `other`.
ThrowIfNegative<T>(T, String)	Throws an ArgumentOutOfRangeException if `value` is negative.
ThrowIfNegativeOrZero<T>(T, String)	Throws an ArgumentOutOfRangeException if `value` is negative or zero.
ThrowIfNotEqual<T>(T, T, String)	Throws an ArgumentOutOfRangeException if `value` is not equal to `other`.
ThrowIfZero<T>(T, String)	Throws an ArgumentOutOfRangeException if `value` is zero.
ToString()	Creates and returns a string representation of the current exception. (Inherited from Exception)

Events

SerializeObjectState

Obsolete.

Occurs when an exception is serialized to create an exception state object that contains serialized data about the exception.

(Inherited from Exception)

Applies to

Dela via