String.Substring Method (Int32, Int32)
Retrieves a substring from this instance. The substring starts at a specified character position and has a specified length.
Namespace: System
Assembly: mscorlib (in mscorlib.dll)
Parameters
- startIndex
- Type: System.Int32
The zero-based starting character position of a substring in this instance.
- length
- Type: System.Int32
The number of characters in the substring.
Return Value
Type: System.StringA string that is equivalent to the substring of length length that begins at startIndex in this instance, or Empty if startIndex is equal to the length of this instance and length is zero.
| Exception | Condition |
|---|---|
| ArgumentOutOfRangeException | startIndex plus length indicates a position not within this instance. -or- startIndex or length is less than zero. |
NoteThe following example uses the Substring method in three cases to isolate substrings within a string. In two cases the substrings are used in comparisons, and in the third case an exception is thrown because invalid parameters are specified.
String myString = "abc"; bool test1 = myString.Substring(2, 1).Equals("c"); // This is true. Console.WriteLine(test1); bool test2 = String.IsNullOrEmpty(myString.Substring(3, 0)); // This is true. Console.WriteLine(test2); try { string str3 = myString.Substring(3, 1); // This throws ArgumentOutOfRangeException. Console.WriteLine(str3); } catch (ArgumentOutOfRangeException e) { Console.WriteLine(e.Message); }
Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
