public void RelativePath()
{
Assert.AreEqual(@"folder2\folder3", ProjectPath.RelativePath(
@"c:\folder1", @"c:\folder1\folder2\folder3"));
Assert.AreEqual(@"..\folder2\folder3", ProjectPath.RelativePath(
@"c:\folder1", @"c:\folder2\folder3"));
Assert.AreEqual(@"bin\debug", ProjectPath.RelativePath(
@"c:\folder1", @"bin\debug"));
Assert.IsNull(ProjectPath.RelativePath(@"C:\folder", @"D:\folder"),
"Unrelated paths should return null");
}