I would like to compare two strings containing file paths in c#.
However, since in ntfs the default is to use case insensitive paths, I would like the string comparison to be case insensitive in the same way.
However I can't seem to find any information on how ntfs actually implements its case insensitivity. What I would like to know is how to perform a case insensitive comparison of strings using the same casing rules that ntfs uses for file paths.
From MSDN:
The string behavior of the file system, registry keys and values, and environment variables is best represented by StringComparison.OrdinalIgnoreCase
.
And:
When interpreting file names, cookies, or anything else where a combination such as "å" can appear, ordinal comparisons still offer the most transparent and fitting behavior.
Therefore it's simply:
String.Equals(fileNameA, fileNameB, StringComparison.OrdinalIgnoreCase)
(I always use the static Equals
call in case the left operand is null
)
string path1 = "C:\\TEST";
string path2 = "c:\\test";
if(path1.ToLower() == path2.ToLower())
MessageBox.Show("True");
Do you mean this or did i not get the question?
I would go for
string.Compare(path1, path2, true) == 0
or if you want to specify cultures:
string.Compare(path1, path2, true, CultureInfo.CurrentCulture) == 0
using ToUpper does a useless memory allocation every time you compare something
While comparison of paths the path's separator direction is also very important. For instance:
bool isEqual = String.Equals("myFolder\myFile.xaml", "myFolder/myFile.xaml", StringComparison.OrdinalIgnoreCase);
isEqual
will be false
.
Therefore needs to fix paths first:
private string FixPath(string path)
{
return path.Replace(Path.DirectorySeparatorChar, Path.AltDirectorySeparatorChar)
.ToUpperInvariant();
}
Whereas this expression will be true
:
bool isEqual = String.Equals(FixPath("myFolder\myFile.xaml"), FixPath("myFolder/myFile.xaml"), StringComparison.OrdinalIgnoreCase);