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Enum.Parse Method

  • Reference

Definition

Namespace:
System
Assembly:
System.Runtime.dll
Assembly:
mscorlib.dll
Assembly:
netstandard.dll

Converts the string representation of the name or numeric value of one or more enumerated constants to an equivalent enumerated object.

Overloads

Parse(Type, ReadOnlySpan<Char>)

Converts the span of characters representation of the name or numeric value of one or more enumerated constants to an equivalent enumerated object.
Parse(Type, String)

Converts the string representation of the name or numeric value of one or more enumerated constants to an equivalent enumerated object.
Parse(Type, ReadOnlySpan<Char>, Boolean)

Converts the span of characters representation of the name or numeric value of one or more enumerated constants to an equivalent enumerated object. A parameter specifies whether the operation is case-insensitive.
Parse(Type, String, Boolean)

Converts the string representation of the name or numeric value of one or more enumerated constants to an equivalent enumerated object. A parameter specifies whether the operation is case-insensitive.
Parse<TEnum>(String, Boolean)

Converts the string representation of the name or numeric value of one or more enumerated constants specified by TEnum to an equivalent enumerated object. A parameter specifies whether the operation is case-insensitive.
Parse<TEnum>(ReadOnlySpan<Char>, Boolean)

Converts the span of characters representation of the name or numeric value of one or more enumerated constants specified by TEnum to an equivalent enumerated object. A parameter specifies whether the operation is case-insensitive.
Parse<TEnum>(ReadOnlySpan<Char>)

Converts the span of characters representation of the name or numeric value of one or more enumerated constants specified by TEnum to an equivalent enumerated object.
Parse<TEnum>(String)

Converts the string representation of the name or numeric value of one or more enumerated constants specified by TEnum to an equivalent enumerated object.

Parse(Type, ReadOnlySpan<Char>)

Source:
Enum.cs
Source:
Enum.cs
Source:
Enum.cs

Converts the span of characters representation of the name or numeric value of one or more enumerated constants to an equivalent enumerated object.

public:
 static System::Object ^ Parse(Type ^ enumType, ReadOnlySpan<char> value);
public static object Parse (Type enumType, ReadOnlySpan<char> value);
static member Parse : Type * ReadOnlySpan<char> -> obj
Public Shared Function Parse (enumType As Type, value As ReadOnlySpan(Of Char)) As Object

Parameters

enumType
Type

An enumeration type.

value
ReadOnlySpan<Char>

A span containing the name or value to convert.

Returns

Object

An object of type enumType whose value is represented by value.

Exceptions

ArgumentNullException

enumType is null.

ArgumentException

enumType is not an Enum.

ArgumentException

value is either an empty string or only contains white space.

ArgumentException

value is a name, but not one of the named constants defined for the enumeration.

OverflowException

value is outside the range of the underlying type of enumType.

InvalidOperationException

.NET 8 and later versions: enumType is a Boolean-backed enumeration type.

Applies to

Parse(Type, String)

Source:
Enum.cs
Source:
Enum.cs
Source:
Enum.cs

Converts the string representation of the name or numeric value of one or more enumerated constants to an equivalent enumerated object.

public:
 static System::Object ^ Parse(Type ^ enumType, System::String ^ value);
public static object Parse (Type enumType, string value);
[System.Runtime.InteropServices.ComVisible(true)]
public static object Parse (Type enumType, string value);
static member Parse : Type * string -> obj
[<System.Runtime.InteropServices.ComVisible(true)>]
static member Parse : Type * string -> obj
Public Shared Function Parse (enumType As Type, value As String) As Object

Parameters

enumType
Type

An enumeration type.

value
String

A string containing the name or value to convert.

Returns

Object

An object of type enumType whose value is represented by value.

Attributes
ComVisibleAttribute

Exceptions

ArgumentNullException

enumType or value is null.

ArgumentException

enumType is not an Enum.

-or-

value is either an empty string or only contains white space.

-or-

value is a name, but not one of the named constants defined for the enumeration.

OverflowException

value is outside the range of the underlying type of enumType.

InvalidOperationException

.NET 8 and later versions: enumType is a Boolean-backed enumeration type.

Examples

The following example uses the Parse(Type, String) method to parse an array of strings that are created by calling the GetNames method. It also uses the Parse(Type, String) method to parse an enumeration value that consists of a bit field.

using namespace System;

[Flags]
enum class Colors
{
   Red = 1,
   Green = 2,
   Blue = 4,
   Yellow = 8
};

int main()
{
   Console::WriteLine(  "The entries of the Colors enumeration are:" );
   Array^ a = Enum::GetNames( Colors::typeid );
   Int32 i = 0;
   while ( i < a->Length )
   {
      Object^ o = a->GetValue( i );
      Console::WriteLine( o->ToString() );
      i++;
   }

   Console::WriteLine();
   Object^ orange = Enum::Parse( Colors::typeid,  "Red, Yellow" );
   Console::WriteLine("The orange value has the combined entries of {0}", orange );
}

/*
This code example produces the following results:

The entries of the Colors Enum are:
Red
Green
Blue
Yellow

The orange value has the combined entries of Red, Yellow

*/

using System;

public class ParseTest
{
    [Flags]
    enum Colors { Red = 1, Green = 2, Blue = 4, Yellow = 8 };

    public static void Main()
    {
        Console.WriteLine("The entries of the Colors enumeration are:");
        foreach (string colorName in Enum.GetNames(typeof(Colors)))
        {
            Console.WriteLine("{0} = {1:D}", colorName,
                                         Enum.Parse(typeof(Colors), colorName));
        }
        Console.WriteLine();

        Colors orange = (Colors) Enum.Parse(typeof(Colors), "Red, Yellow");
        Console.WriteLine("The orange value {0:D} has the combined entries of {0}",
                           orange);
    }
}

/*
This code example produces the following results:

The entries of the Colors Enum are:
Red = 1
Green = 2
Blue = 4
Yellow = 8

The orange value 9 has the combined entries of Red, Yellow

*/

open System

[<Flags>]
type Colors =
    | Red = 1
    | Green = 2
    | Blue = 4
    | Yellow = 8

printfn "The entries of the Colors enumeration are:"
for colorName in Enum.GetNames typeof<Colors> do
    printfn $"{colorName} = {Enum.Parse(typeof<Colors>, colorName):D}"
printfn ""

let orange = Enum.Parse(typeof<Colors>, "Red, Yellow") :?> Colors
printfn $"The orange value {orange:D} has the combined entries of {orange}"

// This code example produces the following results:
//     The entries of the Colors Enum are:
//     Red = 1
//     Green = 2
//     Blue = 4
//     Yellow = 8
//    
//     The orange value 9 has the combined entries of Red, Yellow

Public Class ParseTest

    <Flags()> _
    Enum Colors
        Red = 1
        Green = 2
        Blue = 4
        Yellow = 8
    End Enum

    Public Shared Sub Main()
        Console.WriteLine("The entries of the Colors enumeration are:")
        Dim colorName As String
        For Each colorName In [Enum].GetNames(GetType(Colors))
            Console.WriteLine("{0} = {1:D}", colorName, [Enum].Parse(GetType(Colors), colorName))
        Next
        Console.WriteLine()

        Dim orange As Colors = CType([Enum].Parse(GetType(Colors), "Red, Yellow"), Colors)
        Console.WriteLine("The orange value {0:D} has the combined entries of {0}", orange)
    End Sub
End Class

'This example displays the following output:
'
'The entries of the Colors Enum are:
'Red = 1
'Green = 2
'Blue = 4
'Yellow = 8
'
'The myOrange value 9 has the combined entries of Red, Yellow
'

Remarks

The value parameter contains the string representation of an enumeration member's underlying value or named constant, or a list of named constants delimited by commas (,). One or more blank spaces can precede or follow each value, name, or comma in value. If value is a list, the return value is the value of the specified names combined with a bitwise OR operation.

If value is a name that does not correspond to a named constant of enumType, the method throws an ArgumentException. If value is the string representation of an integer that does not represent an underlying value of the enumType enumeration, the method returns an enumeration member whose underlying value is value converted to an integral type. If this behavior is undesirable, call the IsDefined method to ensure that a particular string representation of an integer is actually a member of enumType. The following example defines a Colors enumeration, calls the Parse(Type, String) method to convert strings to their corresponding enumeration values, and calls the IsDefined method to ensure that particular integral values are underlying values in the Colors enumeration.

using System;

[Flags] enum Colors { None=0, Red = 1, Green = 2, Blue = 4 };

public class Example
{
   public static void Main()
   {
      string[] colorStrings = { "0", "2", "8", "blue", "Blue", "Yellow", "Red, Green" };
      foreach (string colorString in colorStrings)
      {
         try {
            Colors colorValue = (Colors) Enum.Parse(typeof(Colors), colorString);
            if (Enum.IsDefined(typeof(Colors), colorValue) | colorValue.ToString().Contains(","))
               Console.WriteLine("Converted '{0}' to {1}.", colorString, colorValue.ToString());
            else
               Console.WriteLine("{0} is not an underlying value of the Colors enumeration.", colorString);
         }
         catch (ArgumentException) {
            Console.WriteLine("'{0}' is not a member of the Colors enumeration.", colorString);
         }
      }
   }
}
// The example displays the following output:
//       Converted '0' to None.
//       Converted '2' to Green.
//       8 is not an underlying value of the Colors enumeration.
//       'blue' is not a member of the Colors enumeration.
//       Converted 'Blue' to Blue.
//       'Yellow' is not a member of the Colors enumeration.
//       Converted 'Red, Green' to Red, Green.

open System

[<Flags>]
type Colors =
    | None = 0
    | Red = 1
    | Green = 2
    | Blue = 4

let colorStrings = [ "0"; "2"; "8"; "blue"; "Blue"; "Yellow"; "Red, Green" ]
for colorString in colorStrings do
    try
        let colorValue = Enum.Parse(typeof<Colors>, colorString) :?> Colors
        if Enum.IsDefined(typeof<Colors>, colorValue) || (string colorValue).Contains "," then
            printfn $"Converted '{colorString}' to {colorValue}."
        else
            printfn $"{colorString} is not an underlying value of the Colors enumeration."
    with :? ArgumentException ->
        printfn $"'{colorString}' is not a member of the Colors enumeration."
// The example displays the following output:
//       Converted '0' to None.
//       Converted '2' to Green.
//       8 is not an underlying value of the Colors enumeration.
//       'blue' is not a member of the Colors enumeration.
//       Converted 'Blue' to Blue.
//       'Yellow' is not a member of the Colors enumeration.
//       Converted 'Red, Green' to Red, Green.

<Flags> Enum Colors As Integer
   None = 0
   Red = 1
   Green = 2
   Blue = 4
End Enum

Module Example
   Public Sub Main()
      Dim colorStrings() As String = {"0", "2", "8", "blue", "Blue", "Yellow", "Red, Green"}
      For Each colorString As String In colorStrings
         Try
            Dim colorValue As Colors = CType([Enum].Parse(GetType(Colors), colorString), Colors)        
            If [Enum].IsDefined(GetType(Colors), colorValue) Or colorValue.ToString().Contains(",") Then 
               Console.WriteLine("Converted '{0}' to {1}.", colorString, colorValue.ToString())
            Else
               Console.WriteLine("{0} is not an underlying value of the Colors enumeration.", colorString)            
            End If                    
         Catch e As ArgumentException
            Console.WriteLine("'{0}' is not a member of the Colors enumeration.", colorString)
         End Try
      Next
   End Sub
End Module
' The example displays the following output:
'       Converted '0' to None.
'       Converted '2' to Green.
'       8 is not an underlying value of the Colors enumeration.
'       'blue' is not a member of the Colors enumeration.
'       Converted 'Blue' to Blue.
'       'Yellow' is not a member of the Colors enumeration.
'       Converted 'Red, Green' to Red, Green.

This operation is case-sensitive.

See also

Applies to

Parse(Type, ReadOnlySpan<Char>, Boolean)

Source:
Enum.cs
Source:
Enum.cs
Source:
Enum.cs

Converts the span of characters representation of the name or numeric value of one or more enumerated constants to an equivalent enumerated object. A parameter specifies whether the operation is case-insensitive.

public:
 static System::Object ^ Parse(Type ^ enumType, ReadOnlySpan<char> value, bool ignoreCase);
public static object Parse (Type enumType, ReadOnlySpan<char> value, bool ignoreCase);
static member Parse : Type * ReadOnlySpan<char> * bool -> obj
Public Shared Function Parse (enumType As Type, value As ReadOnlySpan(Of Char), ignoreCase As Boolean) As Object

Parameters

enumType
Type

An enumeration type.

value
ReadOnlySpan<Char>

A span containing the name or value to convert.

ignoreCase
Boolean

true to ignore case; false to regard case.

Returns

Object

An object of type enumType whose value is represented by value.

Exceptions

ArgumentNullException

enumType is null.

ArgumentException

enumType is not an Enum.

ArgumentException

value is either an empty string or only contains white space.

ArgumentException

value is a name, but not one of the named constants defined for the enumeration.

OverflowException

value is outside the range of the underlying type of enumType

InvalidOperationException

.NET 8 and later versions: enumType is a Boolean-backed enumeration type.

Applies to

Parse(Type, String, Boolean)

Source:
Enum.cs
Source:
Enum.cs
Source:
Enum.cs

Converts the string representation of the name or numeric value of one or more enumerated constants to an equivalent enumerated object. A parameter specifies whether the operation is case-insensitive.

public:
 static System::Object ^ Parse(Type ^ enumType, System::String ^ value, bool ignoreCase);
public static object Parse (Type enumType, string value, bool ignoreCase);
[System.Runtime.InteropServices.ComVisible(true)]
public static object Parse (Type enumType, string value, bool ignoreCase);
static member Parse : Type * string * bool -> obj
[<System.Runtime.InteropServices.ComVisible(true)>]
static member Parse : Type * string * bool -> obj
Public Shared Function Parse (enumType As Type, value As String, ignoreCase As Boolean) As Object

Parameters

enumType
Type

An enumeration type.

value
String

A string containing the name or value to convert.

ignoreCase
Boolean

true to ignore case; false to regard case.

Returns

Object

An object of type enumType whose value is represented by value.

Attributes
ComVisibleAttribute

Exceptions

ArgumentNullException

enumType or value is null.

ArgumentException

enumType is not an Enum.

-or-

value is either an empty string ("") or only contains white space.

-or-

value is a name, but not one of the named constants defined for the enumeration.

OverflowException

value is outside the range of the underlying type of enumType.

InvalidOperationException

.NET 8 and later versions: enumType is a Boolean-backed enumeration type.

Examples

The following example uses the Parse(Type, String, Boolean) method to parse an array of strings that are created by calling the GetNames method. It also uses the Parse(Type, String) method to parse an enumeration value that consists of a bit field.

using System;

[Flags] enum Colors { None=0, Red = 1, Green = 2, Blue = 4 };

public class Example
{
   public static void Main()
   {
      string[] colorStrings = { "0", "2", "8", "blue", "Blue", "Yellow", "Red, Green" };
      foreach (string colorString in colorStrings)
      {
         try {
            Colors colorValue = (Colors) Enum.Parse(typeof(Colors), colorString, true);
            if (Enum.IsDefined(typeof(Colors), colorValue) | colorValue.ToString().Contains(","))
               Console.WriteLine("Converted '{0}' to {1}.", colorString, colorValue.ToString());
            else
               Console.WriteLine("{0} is not an underlying value of the Colors enumeration.", colorString);
         }
         catch (ArgumentException) {
            Console.WriteLine("{0} is not a member of the Colors enumeration.", colorString);
         }
      }
   }
}
// The example displays the following output:
//       Converted '0' to None.
//       Converted '2' to Green.
//       8 is not an underlying value of the Colors enumeration.
//       Converted 'blue' to Blue.
//       Converted 'Blue' to Blue.
//       Yellow is not a member of the Colors enumeration.
//       Converted 'Red, Green' to Red, Green.

open System

[<Flags>]
type Colors =
    | None = 0
    | Red = 1
    | Green = 2
    | Blue = 4

let colorStrings = [ "0"; "2"; "8"; "blue"; "Blue"; "Yellow"; "Red, Green" ]
for colorString in colorStrings do
    try
        let colorValue = Enum.Parse(typeof<Colors>, colorString, true) :?> Colors
        if Enum.IsDefined(typeof<Colors>, colorValue) || (string colorValue).Contains "," then
            printfn $"Converted '{colorString}' to {colorValue}."
        else
            printfn $"{colorString} is not an underlying value of the Colors enumeration."
    with :? ArgumentException ->
        printfn $"{colorString} is not a member of the Colors enumeration."

// The example displays the following output:
//       Converted '0' to None.
//       Converted '2' to Green.
//       8 is not an underlying value of the Colors enumeration.
//       Converted 'blue' to Blue.
//       Converted 'Blue' to Blue.
//       Yellow is not a member of the Colors enumeration.
//       Converted 'Red, Green' to Red, Green.

<Flags> Enum Colors As Integer
   None = 0
   Red = 1
   Green = 2
   Blue = 4
End Enum

Module Example
   Public Sub Main()
      Dim colorStrings() As String = {"0", "2", "8", "blue", "Blue", "Yellow", "Red, Green"}
      For Each colorString As String In colorStrings
         Try
            Dim colorValue As Colors = CType([Enum].Parse(GetType(Colors), colorString, True), Colors)        
            If [Enum].IsDefined(GetType(Colors), colorValue) Or colorValue.ToString().Contains(",") Then 
               Console.WriteLine("Converted '{0}' to {1}.", colorString, colorValue.ToString())
            Else
               Console.WriteLine("{0} is not an underlying value of the Colors enumeration.", colorString)            
            End If                    
         Catch e As ArgumentException
            Console.WriteLine("{0} is not a member of the Colors enumeration.", colorString)
         End Try
      Next
   End Sub
End Module
' The example displays the following output:
'       Converted '0' to None.
'       Converted '2' to Green.
'       8 is not an underlying value of the Colors enumeration.
'       Converted 'blue' to Blue.
'       Converted 'Blue' to Blue.
'       Yellow is not a member of the Colors enumeration.
'       Converted 'Red, Green' to Red, Green.

Remarks

The value parameter contains the string representation of an enumeration member's underlying value or named constant, or a list of named constants delimited by commas (,). One or more blank spaces can precede or follow each value, name, or comma in value. If value is a list, the return value is the value of the specified names combined with a bitwise OR operation.

If value is a name that does not correspond to a named constant of enumType, the method throws an ArgumentException. If value is the string representation of an integer that does not represent an underlying value of the enumType enumeration, the method returns an enumeration member whose underlying value is value converted to an integral type. If this behavior is undesirable, call the IsDefined method to ensure that a particular string representation of an integer is actually a member of enumType. The following example defines a Colors enumeration, calls the Parse(Type, String, Boolean) method to convert strings to their corresponding enumeration values, and calls the IsDefined method to ensure that particular integral values are underlying values in the Colors enumeration.

The ignoreCase parameter specifies whether this operation is case-sensitive.

See also

Applies to

Parse<TEnum>(String, Boolean)

Source:
Enum.cs
Source:
Enum.cs
Source:
Enum.cs

Converts the string representation of the name or numeric value of one or more enumerated constants specified by TEnum to an equivalent enumerated object. A parameter specifies whether the operation is case-insensitive.

public:
generic <typename TEnum>
 where TEnum : value class static TEnum Parse(System::String ^ value, bool ignoreCase);
public static TEnum Parse<TEnum> (string value, bool ignoreCase) where TEnum : struct;
static member Parse : string * bool -> 'Enum (requires 'Enum : struct)
Public Shared Function Parse(Of TEnum As Structure) (value As String, ignoreCase As Boolean) As TEnum

Type Parameters

TEnum

An enumeration type.

Parameters

value
String

A string containing the name or value to convert.

ignoreCase
Boolean

true to ignore case; false to regard case.

Returns

TEnum

An object of type TEnum whose value is represented by value.

Exceptions

ArgumentException

TEnum is not an Enum type.

ArgumentNullException

value is null.

ArgumentException

value does not contain enumeration information.

InvalidOperationException

.NET 8 and later versions: TEnum is a Boolean-backed enumeration type.

Applies to

Parse<TEnum>(ReadOnlySpan<Char>, Boolean)

Source:
Enum.cs
Source:
Enum.cs
Source:
Enum.cs

Converts the span of characters representation of the name or numeric value of one or more enumerated constants specified by TEnum to an equivalent enumerated object. A parameter specifies whether the operation is case-insensitive.

public:
generic <typename TEnum>
 where TEnum : value class static TEnum Parse(ReadOnlySpan<char> value, bool ignoreCase);
public static TEnum Parse<TEnum> (ReadOnlySpan<char> value, bool ignoreCase) where TEnum : struct;
static member Parse : ReadOnlySpan<char> * bool -> 'Enum (requires 'Enum : struct)
Public Shared Function Parse(Of TEnum As Structure) (value As ReadOnlySpan(Of Char), ignoreCase As Boolean) As TEnum

Type Parameters

TEnum

An enumeration type.

Parameters

value
ReadOnlySpan<Char>

A span containing the name or value to convert.

ignoreCase
Boolean

true to ignore case; false to regard case.

Returns

TEnum

TEnum An object of type TEnum whose value is represented by value.

Exceptions

ArgumentException

TEnum is not an Enum type.

ArgumentException

value does not contain enumeration information.

InvalidOperationException

.NET 8 and later versions: TEnum is a Boolean-backed enumeration type.

Applies to

Parse<TEnum>(ReadOnlySpan<Char>)

Source:
Enum.cs
Source:
Enum.cs
Source:
Enum.cs

Converts the span of characters representation of the name or numeric value of one or more enumerated constants specified by TEnum to an equivalent enumerated object.

public:
generic <typename TEnum>
 where TEnum : value class static TEnum Parse(ReadOnlySpan<char> value);
public static TEnum Parse<TEnum> (ReadOnlySpan<char> value) where TEnum : struct;
static member Parse : ReadOnlySpan<char> -> 'Enum (requires 'Enum : struct)
Public Shared Function Parse(Of TEnum As Structure) (value As ReadOnlySpan(Of Char)) As TEnum

Type Parameters

TEnum

An enumeration type.

Parameters

value
ReadOnlySpan<Char>

A span containing the name or value to convert.

Returns

TEnum

TEnum An object of type TEnum whose value is represented by value.

Exceptions

ArgumentException

TEnum is not an Enum type.

ArgumentException

value does not contain enumeration information.

InvalidOperationException

.NET 8 and later versions: TEnum is a Boolean-backed enumeration type.

Applies to

Parse<TEnum>(String)

Source:
Enum.cs
Source:
Enum.cs
Source:
Enum.cs

Converts the string representation of the name or numeric value of one or more enumerated constants specified by TEnum to an equivalent enumerated object.

public:
generic <typename TEnum>
 where TEnum : value class static TEnum Parse(System::String ^ value);
public static TEnum Parse<TEnum> (string value) where TEnum : struct;
static member Parse : string -> 'Enum (requires 'Enum : struct)
Public Shared Function Parse(Of TEnum As Structure) (value As String) As TEnum

Type Parameters

TEnum

An enumeration type.

Parameters

value
String

A string containing the name or value to convert.

Returns

TEnum

An object of type TEnum whose value is represented by value.

Exceptions

ArgumentException

TEnum is not an Enum type.

ArgumentNullException

value is null.

ArgumentException

value does not contain enumeration information.

InvalidOperationException

.NET 8 and later versions: TEnum is a Boolean-backed enumeration type.

Applies to