Returns the extension of the specified path string.
Syntax
Parameters
- path
Returns
The extension of the specified path (including the period "."), or null, or string.Empty. If path is null, Path.GetExtension(string) returns null. If path does not have extension information, Path.GetExtension(string) returns string.Empty.
Exceptions
Type Reason ArgumentException path contains one or more implementation-specific invalid characters.
Remarks
The extension of path is obtained by searching path for a period (.), starting with the last character in path and continuing toward the start of path. If a period is found before a Path.DirectorySeparatorChar or Path.AltDirectorySeparatorChar character, the returned string contains the period and the characters after it; otherwise, string.Empty is returned.
For a list of common I/O tasks, see Common I/O Tasks.
Example
The following example demonstrates using the Path.GetExtension(string) method on a Windows system.
C# Example
using System;
using System.IO;
class GetDirectoryTest {
public static void Main(){
string [] paths = {
@"\ecmatest\examples\pathtests.txt",
@"\ecmatest\examples\",
"pathtests.xyzzy",
"pathtests.xyzzy.txt",
@"\",
""
};
foreach (string pathString in paths){
string s = Path.GetExtension (pathString);
if (s == String.Empty) s= "(empty string)";
if (s == null) s= "null";
Console.WriteLine("{0} is the extension of {1}", s, pathString);
}
}
}
The output is
.txt is the extension of \ecmatest\examples\pathtests.txt(empty string) is the extension of \ecmatest\examples\
.xyzzy is the extension of pathtests.xyzzy
.txt is the extension of pathtests.xyzzy.txt
(empty string) is the extension of \
(empty string) is the extension of
Requirements
Assembly: mscorlib (in mscorlib.dll)
Assembly Versions: 1.0.5000.0, 2.0.0.0, 4.0.0.0