Question

I have the following code:

    content = Regex.Replace(content, "{%Pwd%}", pwd ?? "");

If pwd is null, I would expect it to be replaced with “” but it is still pulling it in as null.
Anyway, I can fix this. Also why is it not working as expected?

Answer 1

First of all I’d split this line into two:

string replacement = pwd ?? "";
content = Regex.Replace(content, "{%Pwd%}", replacement);

• What is the value of replacement?
• Is content being replaced with "null"?

I’m guessing it will be "null" or "" as if replacement was null an ArgumentNullException would be thrown.

I’d also check that {%Pwd%} is the correct regular expression – becuase Expresso doesn’t recognise it, it well may need certain characters escaping. Without content we can only guess.

If you check these things the answer should become apparent.