/// <summary>

/// Generates a new path for duplicate filenames.

/// </summary>

/// <param name="path">The path.</param>

/// <returns></returns>

private string GetNewPathForDupes( string path )

{

    string directory = Path.GetDirectoryName( path );

    string filename = Path.GetFileNameWithoutExtension( path );

    string extension = Path.GetExtension( path );

    int counter = ;

    string newFullPath;

    do

    {

    string newFilename = "{0}({1}).{2}".FormatWith( filename, counter, extension );

    newFullPath = Path.Combine( directory, newFilename );

    counter++;

    } while ( System.IO.File.Exists( newFullPath ) );

    return newFullPath;

}

源地址：http://www.oschina.net/code/snippet_4873_1460