String.IndexOf Method (Char)
Assembly: mscorlib (in mscorlib.dll)
Index numbering starts from zero.
The search for value 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 values 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.
The following code example demonstrates how you can search a String for a character using the IndexOf method.
// Create a Unicode String with 5 Greek Alpha characters String szGreekAlpha = new String('\u0319',5); // Create a Unicode String with a Greek Omega character String szGreekOmega = new String(new char [] {'\u03A9','\u03A9','\u03A9'},2,1); String szGreekLetters = String.Concat(szGreekOmega, szGreekAlpha, szGreekOmega.Clone()); // Examine the result Console.WriteLine(szGreekLetters); // The first index of Alpha int ialpha = szGreekLetters.IndexOf('\u0319'); // The last index of Omega int iomega = szGreekLetters.LastIndexOf('\u03A9'); Console.WriteLine("The Greek letter Alpha first appears at index " + ialpha + " and Omega last appears at index " + iomega + " in this String.");
Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.