__dirname doesn't work in a regex

Question

I am trying to remove __dirname from a directory I need to copy (recursively). I gather information about the problem:

console.log(typeof __dirname); // string
console.log(__dirname); // c:\test

I need to create the regex from a string I get from the program. Therefore I must use RegExp(myString). I do a reality check on jsfiddle to make sure the right way to escape \ is with \/ fiddle.

I run the code in the browser and it works. I run the code in node.js and it does not work. I take this to the extreme by trying to remove RegExp(__dirname) from __dirname.

If you have a string var s = __dirname.toString() + "myOtherPath/a.cat" how do you remove the __dirname part of the string from s?

why can't your just use replace or substring(dirname_length)? — gp., Oct 07 '13 at 04:12
im not sure if the paths i use will be different from the paths my server uses. if they use paths with different lengths it would break. — user1873073, Oct 07 '13 at 04:17
Can you show your actual code where you are using `new RegExp`? — Brad, Oct 07 '13 at 04:17
what about: `if(s.indexof(__dirname)==0) s.substring(__dirname.length);` — gp., Oct 07 '13 at 04:25
gp, no good because i dont know if the paths change once i upload them. i could test but if they change things later ill have to do this again. — user1873073, Oct 07 '13 at 04:28

user568109 · Accepted Answer · 2013-10-07T05:28:32.520

1

Your regex example is wrong. The regex is for removing backslash. But the string itself does not have either backslash or slash.

var y = "c:\y";
//"c:y"

To correctly add backslash you have to

var y = "c:\\y";
//"c:\y"

Your example would have worked in linux where the separator is /, which does not need to be escaped. Besides it looks like you are doing substring replace not regex replace. So simply giving the __dirname in replace would suffice :

var y = __dirname;
var z = y.replace(__dirname,"").toString();

edited Oct 07 '13 at 05:28

answered Oct 07 '13 at 05:16

user568109

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If you want to search a string via regex see this [question](http://stackoverflow.com/questions/3561493/is-there-a-regexp-escape-function-in-javascript) – user568109 Oct 07 '13 at 09:21
@user1873073 You are printing y, print z. – user568109 Oct 07 '13 at 14:14

__dirname doesn't work in a regex

1 Answers1