public static string GetCommonPathPrefix(string path1, string path2)
{
Validate.IsNotNull(path1, "path1");
Validate.IsNotNull(path2, "path2");
if (path1.Length == 0 || path2.Length == 0)
{
return(string.Empty);
}
if (ArePathsEqual(path1, path2))
{
return(path1);
}
bool flag = path1.StartsWith("\\\\");
if (flag != path2.StartsWith("\\\\"))
{
return(string.Empty);
}
using (ReusableResourceHolder <StringBuilder> reusableResourceHolder = ReusableStringBuilder.AcquireDefault(260))
{
StringBuilder resource = reusableResourceHolder.Resource;
PathParser pathParser = new PathParser(path1);
PathParser other = new PathParser(path2);
while (pathParser.MoveNext() && other.MoveNext() && (pathParser.CurrentLength == other.CurrentLength && pathParser.CompareCurrentSegment(other) == 0))
{
if (resource.Length == 0 & flag)
{
resource.Append("\\\\");
}
else if (resource.Length > 0)
{
resource.Append(Path.DirectorySeparatorChar);
}
resource.Append(path1, pathParser.CurrentStartIndex, pathParser.CurrentLength);
}
if (resource.Length == 2 && resource[1] == Path.VolumeSeparatorChar)
{
resource.Append('\\');
}
return(resource.ToString());
}
}