Question

Am i doing sth wrong or there is a problem with JS replace ?

<input type="text" id="a" value="(55) 55-55-55" />​

document.write($("#a").val().replace(/()-/g,''));​

prints (55) 555555

http://jsfiddle.net/Yb2yV/

how can i replace () and spaces too?

Answer 1

In a JavaScript regular expression, the ( and ) characters have special meaning. If you want to list them literally, put a backslash (\) in front of them.

If your goal is to get rid of all the (, ), -, and space characters, you could do it with a character class combined with an alternation (e.g., either-or) on \s, which stands for “whitespace”:

document.write($("#a").val().replace(/[()\-]|\s/g,''));​

(I didn’t put backslashes in front of the () because you don’t need to within a character class. I did put one in front of the - because within a character class, - has special meaning.)

Alternately, if you want to get rid of anything that isn’t a digit, you can use \D:

document.write($("#a").val().replace(/\D/g,''));​

\D means “not a digit” (note that it’s a capital, \d in lower case is the opposite [any digit]).

More info on the MDN page on regular expressions.