A Generic Diff/Patch Utility written in C#

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Introduction

Have you ever wanted or needed a diff and/or patch utility optimized for the .NET platform.

This article provides an implementation of a diff/patch utility written in C#.

It operates over generics, so you can provide lists of anything to be diffed or patched,
including strings (such as lines from files), int, objects, or even bytes.

The implementation also provides a command line interface with output similar to the UNIX diff command.

Example of using the Diff class to diff 2 text files

List<string> a = new List<string>();
List<string> b = new List<string>();
StreamReader fs1 = new StreamReader(argv[0]);
StreamReader fs2 = new StreamReader(argv[1]);
string line;
while ((line = fs1.ReadLine()) != null)
{
	a.Add(line);
}
while ((line = fs2.ReadLine()) != null)
{
	b.Add(line);
}
fs1.Dispose();
fs2.Dispose();
Diff<string> diff = new Diff<string>(a, b, true);

This performs the diff.  The final parameter indicates whether the actual differences should be included in the edit script when the diff is performed.

To write the differences between file A and file B to the console,

diff.Write(Console.Out);

Patching an input or Converting A into B

To Patch a file by applying the diff edit script changes to an input, use the Patch Class

Patch<string> patch = new Patch<string>(a, diff.SES);
foreach (string line in patch.Lines)
{
	Console.WriteLine(line);
}