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String.IndexOfAny Method (array<Char[], Int32, Int32)

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Reports the zero-based index of the first occurrence in this instance of any character in a specified array of Unicode characters. The search starts at a specified character position and examines a specified number of character positions.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

Syntax

'Declaration
<SecuritySafeCriticalAttribute> _
Public Function IndexOfAny ( _
    anyOf As Char(), _
    startIndex As Integer, _
    count As Integer _
) As Integer
[SecuritySafeCriticalAttribute]
public int IndexOfAny(
    char[] anyOf,
    int startIndex,
    int count
)

Parameters

  • anyOf
    Type: array<System.Char[]
    A Unicode character array containing one or more characters to seek.
  • startIndex
    Type: System.Int32
    The search starting position.
  • count
    Type: System.Int32
    The number of character positions to examine.

Return Value

Type: System.Int32
The zero-based index position of the first occurrence in this instance where any character in anyOf was found; otherwise, -1 if no character in anyOf was found.

Exceptions

Exception Condition
ArgumentNullException

anyOf is nulla null reference (Nothing in Visual Basic).

ArgumentOutOfRangeException

count or startIndex is negative.

-or-

count + startIndex is greater than the number of characters in this instance.

Remarks

The search begins at startIndex and continues to startIndex + count -1. The character at startIndex + count is not included in the search.

Index numbering starts from zero. startIndex can range from 0 to one less than the length of the string instance.

The search for anyOf is case-sensitive.

This method performs an ordinal (culture-insensitive) search, where a character is considered equivalent to another character only if their Unicode scalar value are the same. To perform a culture-sensitive search, use the CompareInfo.IndexOf method, where a Unicode scalar value representing a precomposed character, such as the ligature 'Æ' (U+00C6), might be considered equivalent to any occurrence of the character's components in the correct sequence, such as "AE" (U+0041, U+0045), depending on the culture.

Platform Notes

Silverlight for Windows Phone Silverlight for Windows Phone

 If you pass an invalid parameter value, IndexOfAny throws an ArgumentOutOfRangeException instead of an ArgumentNullException.

Examples

The following code example finds the index of the occurrence of any character of the string "aid" within a substring of another string.

' Sample for String.IndexOfAny(Char[], Int32, Int32)

Class Example
   Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
      Dim br1 As String = "0----+----1----+----2----+----3----+----4----+----5----+----6----+-"
      Dim br2 As String = "0123456789012345678901234567890123456789012345678901234567890123456"
      Dim str As String = "Now is the time for all good men to come to the aid of their party."
      Dim start As Integer
      Dim at As Integer
      Dim count As Integer
      Dim target As String = "aid"
      Dim anyOf As Char() = target.ToCharArray()

      start = (str.Length - 1) / 3
      count = (str.Length - 1) / 4
      outputBlock.Text &= vbCrLf
      outputBlock.Text &= String.Format("The first character occurrence from position {0} for {1} characters.", start, count) & vbCrLf
      outputBlock.Text &= String.Format("{1}{0}{2}{0}{3}{0}", vbCrLf, br1, br2, str) & vbCrLf
      outputBlock.Text &= String.Format("A character in '{0}' occurs at position: ", target)

      at = str.IndexOfAny(anyOf, start, count)
      If at > -1 Then
         outputBlock.Text &= at
      Else
         outputBlock.Text &= "(not found)"
      End If
      outputBlock.Text &= vbCrLf
   End Sub 'Main
End Class 'Sample
'
'The first character occurrence from position 22 for 16 characters.
'0----+----1----+----2----+----3----+----4----+----5----+----6----+-
'0123456789012345678901234567890123456789012345678901234567890123456
'Now is the time for all good men to come to the aid of their party.
'
'A character in 'aid' occurs at position: 27
'
// Sample for String.IndexOfAny(Char[], Int32, Int32)
using System;

class Example
{
   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      string br1 = "0----+----1----+----2----+----3----+----4----+----5----+----6----+-";
      string br2 = "0123456789012345678901234567890123456789012345678901234567890123456";
      string str = "Now is the time for all good men to come to the aid of their party.";
      int start;
      int at;
      int count;
      string target = "aid";
      char[] anyOf = target.ToCharArray();

      start = (str.Length - 1) / 3;
      count = (str.Length - 1) / 4;
      outputBlock.Text += "\n";
      outputBlock.Text += String.Format("The first character occurrence from position {0} for {1} characters.", start, count) + "\n";
      outputBlock.Text += String.Format("{1}{0}{2}{0}{3}{0}", "\n", br1, br2, str) + "\n";
      outputBlock.Text += String.Format("A character in '{0}' occurs at position: ", target);

      at = str.IndexOfAny(anyOf, start, count);
      if (at > -1)
         outputBlock.Text += at;
      else
         outputBlock.Text += "(not found)";
      outputBlock.Text += "\n";
   }
}
/*

The first character occurrence from position 22 for 16 characters.
0----+----1----+----2----+----3----+----4----+----5----+----6----+-
0123456789012345678901234567890123456789012345678901234567890123456
Now is the time for all good men to come to the aid of their party.

A character in 'aid' occurs at position: 27

*/

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.