Home | Google Diff-Match-Patch

Evolution of the C# port of the google diff-match-patch implementation. - https://github.com/google/diff-match-patch

Usage

Given 2 input strings, for example:

var text1 = "start\n"
            "line with some content\n"
            "unchanged content\n"
            "removed line\n"
            "end";

var text2 = "start\n"
            "new line\n"
            "line with some modified content\n"
            "unchanged content\n"
            "end";

We can calculate the differences by doing

var diffs = Diff.Compute(text1, text2);
foreach (var diff in diffs)
{
  Console.WriteLine(diff.ToString().Trim());
}

This would give output of:

Diff(Equal,"start¶")
Diff(Insert,"new·line¶")
Diff(Equal,"line·with·some·")
Diff(Insert,"modified·")
Diff(Equal,"content¶unchanged·content")
Diff(Delete,"¶removed·line")
Diff(Equal,"¶end")

From a diff collection we can create a set of patches:

var patches = Patch.FromDiffs(diffs);
foreach (var patch in patches)
{
  Console.WriteLine(diff.ToString().Trim());
}

This would give output of:

@@ -1,14 +1,23 @@
 start%0a
+new line%0a
 line wit
@@ -23,16 +23,25 @@
 th some 
+modified 
 content%0a
@@ -61,21 +61,8 @@
 tent
-%0aremoved line
 %0aend

It’s also possible to create the patches without diffs

var patches = Patch.Compute(text1, text2);
foreach (var patch in patches)
{
  Console.WriteLine(diff.ToString().Trim());
}

And the output here is the same:

@@ -1,14 +1,23 @@
 start%0a
+new line%0a
 line wit
@@ -23,16 +23,25 @@
 th some 
+modified 
 content%0a
@@ -62,20 +62,7 @@
 ent%0a
-removed line%0a
 end

Once we have the diff or patch output, there are various ‘readable’ formats to output in

diffs.ToHtml();
diffs.ToHtmlDocument();
diffs.ToReadableText();
diffs.ToText();
patches.ToHtml();
patches.ToHtmlDocument();
patches.ToReadableText();
patches.ToText();

These can be displayed on screen or saved to a file within your own code

Example output can be seen in the ApprovalTest output:

Google Diff Match Patch

Usage