Simple JavaScript Regex replace is not working on Token with Square Brackets?

Question

I'm trying to replace the token "[RANDOMNUMBER]" in a string but my code is not working? The regex shows as valid when checking on online validation tools? I know it has to be a stupid mistake but I don't see it?

function detokenizeTags(imgSrc){
    var rn = Math.random() + "",
    rnd = rn * 10000000000000;
    imgSrc.replace(/\[RANDOMNUMBER\]/g,rnd);
    return imgSrc; 
}

sample input string: //ad.amgdgt.com/ads/?t=ap&px=79079&rndn=[RANDOMNUMBER]

And how is it being called exactly? – epascarello Nov 05 '16 at 03:40 — epascarello, Nov 05 '16 at 03:40

score 1 · Accepted Answer · answered Nov 05 '16 at 03:48

1

The problem is the fact the replacement does NOT change the original string.

imgSrc.replace(/\[RANDOMNUMBER\]/g,rnd);

needs to be

imgSrc = imgSrc.replace(/\[RANDOMNUMBER\]/g,rnd);

function detokenizeTags(imgSrc){
    var rn = Math.random() + "",
    rnd = rn * 10000000000000;
    return imgSrc.replace(/\[RANDOMNUMBER\]/g,rnd);
}

var str = "//ad.amgdgt.com/ads/?t=ap&px=79079&rndn=[RANDOMNUMBER]";

console.log(str, detokenizeTags(str));

answered Nov 05 '16 at 03:48

epascarello

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I knew I was doing something stupid! That's what I get for being up for almost two days! Much appreciated! – Michael Johns Nov 05 '16 at 03:55

score 0 · Answer 2 · answered Nov 05 '16 at 03:48

0

.replace doesn't modify the string, it returns a new string. Instead of:

imgSrc.replace(/\[RANDOMNUMBER\]/g,rnd);
return imgSrc;

try just:

return imgSrc.replace(/\[RANDOMNUMBER\]/g,rnd);

answered Nov 05 '16 at 03:48

Chris Simon

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Simple JavaScript Regex replace is not working on Token with Square Brackets?

2 Answers2