Regex to find and replace any word that is not after another word

Question

I'm currently running a simple find-and-replace, on strings like this:

1. User.Name "John"
2. User.Age 20
3. Name.Length 5

However, trying to replace Name with WHATEVER results in this:

1. User.WHATEVER "John"
2. User.Age 20
3. WHATEVER.Length 5

I needed to change line 3, but not line 1. How do I check if the current word is after a dot ( . ) and skip replacing that word?

I'm in .NET 4.0 and my regex currently looks like this:

result = new Regex(@"\b" + oldWord + @"\b").Replace(text, newWord);

Answer 1

You can use a negative lookbehind on . : (?<!\\.)

That gives:

result = new Regex(@"\b(?<!\.)" + oldWord + @"\b").Replace(text, newWord);