Remove single backslashes, convert doubles to single in string

Question

How best can I convert instances of double backslashes to a single backslash in a string, but remove any occurrences of single backslash?

So this:

\|Testing|ABC:1234\\1000-1\|

Should convert to this:

|Testing|ABC:1234\1000-1|

Ideally I want to avoid a temporary replace of '\' to another character. A solution using .NET or Regular Expressions is preferred.

Answer 1

Regex.Replace(input, @"\\(.|$)", "$1");

[Edit: Pattern didn't match all possible cases specified in the OP. Thanks for the suggestions, GONeale and Alan M.]