Question

I’m trying to make an auto-complete function for twitter usernames.

So far, I have the following code:

function OnKeyUp(txtboxid){
    var text = $('#'+txtboxid).val()
    var regex = '(^|\s)@(\w*[a-zA-Z_]+\w*)' 
    var results = text.match(RegExp(regex, 'gm'))
    console.debug(results)
}

The problem is, it matches only text when it is at the beginning of the string (eg: @yser)

What i want is a regex that can mach such a string like this “hello @user2 , @user and @user3 how are you”

I’m not sure how to accomplish this.
Searched google for about 3 hours now and still nothing found.

Also, it would be great to only the the last username when its changed.

Answer 1

Your regex is fine. The only problem is that backslashes in the string will be removed or replaced when the string is parsed, instead of being interpreted by the regular expression parser. You need to re-escape each of them with an extra backslash:

var regex = '(^|\\s)@(\\w*[a-zA-Z_]+\\w*)';

Instead of specifying the regular expression with a string and the RegEx function, you should usually use a regular expression literal. It’s delimited by backslashes instead of double-quotes, with the flags appended to the end:

var results = text.match(/(^|\s)@(\w*[a-zA-Z_]+\w*)/gm);