Odd behaviour replacing “\”

Question

I have this issue in which I have a strnig with among other things the literal expression "\\\\" on several occasions and I want to replace it with "\\" , when I try to replace it with string.replace, only replcaes the first occurrence, and if I do it with regular expression it doesn't replace it at all

I checked with some RegEx Testers online and supposedly my code is ok, returns what I meant to, but my code doesn't work at all

With string.replace

example = "\\\\url.com\\place\\anotherplace\\extraplace\\";

example = example.replace("\\\\","\\");

returns example == "\\url.com\\place\\anotherplace\\extraplace\\";

With RegEx

example = Regex.Replace(example,"\\\\","\\");

returns example = "\\\\url.com\\place\\anotherplace\\extraplace\\";

It is the same case if I use literals (On the Replace function parameters use (@"\\\\", @"\\") gives the same result as above).

Thanks!

EDIT:

I think my ultimate goal was confusing so I'll update it here, what I want to do is:

Input: variable that holds the string: "\\\\\\\\url.com\\\\place\\\\anotherplace\\\\extraplace\\\\"

Process

Output variable that holds the string "\\\\url.com\\place\\anotherplace\\extraplace\\" (so I can send it to ffmpeg and it recognizes it as a valid route)

Answer 1

change this:

example = "\\\\url.com\\place\\anotherplace\\extraplace\\"; 

to this

example = @"\\\\url.com\\place\\anotherplace\\extraplace\\"; 

It wasn't the Regex.Replace parameters that was the problem.

Answer 2

You only have one occurrence of \\\\\\\\ in your string. So it is doing exactly what you asked it to do.

Without escaping (ie without adding extra /'s)

• What is your actual input?
• What is your desired output?

Answer 3

您应该将其更改为以下内容

example = example.replace(@"\\", @"\");

Answer 4

That appears to be the expected behavior.

In the String.Replace case: Initially, example contains a string that starts with two backslashes, and contains a few single backslashes elsewhere in the string. You then attempted to replace all occurrences of double backslashes with a single backslash, which worked and produced a string that starts with a single backslash and contains a few single backslashes elsewhere in the string.

In the Regex.Replace case: The original contents of example are irrelevant in this case. Your regex pattern is a double backslash, which when interpreted as a regex pattern, means "find a single backslash". You then replace this pattern with a single backslash, which results in no change to the string.