regex - JavaScript RegExp - g modifier not working - Stack Overflow

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I have been stuck on this silly issue for hours now. I know it seems stupid but I really don't know what I am missing. Any help would be appreciated.

Here's my issue:

var objReg = /touch/g;
var str = "abc touch def touch";
var arr = objReg.exec(str);

Here I expect the array arr to contain 2 elements but it only contains the 1st element even though I made sure to put the g modifier.

Can anyone guide me what is to be done here?

Debug: As shown in the image below, the array has just 1 element(index=0)

I have been stuck on this silly issue for hours now. I know it seems stupid but I really don't know what I am missing. Any help would be appreciated.

Here's my issue:

var objReg = /touch/g;
var str = "abc touch def touch";
var arr = objReg.exec(str);

Here I expect the array arr to contain 2 elements but it only contains the 1st element even though I made sure to put the g modifier.

Can anyone guide me what is to be done here?

Debug: As shown in the image below, the array has just 1 element(index=0)

• javascript
• regex
• jscript
• testplete

Share Improve this question Follow edited Nov 1, 2017 at 17:41 Scott Marcus 65.9k66 gold badges5353 silver badges8080 bronze badges asked Nov 1, 2017 at 17:32 ManJoeyManJoey 21333 silver badges77 bronze badges 1

• 2 You have to repeat RegExp.exec until the returned value is null. Alternatively, you can use str.match(re), which returns just the array of matches. – Marko Gresak Commented Nov 1, 2017 at 17:36

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2 Answers 2

Sorted by: Reset to default 7

To get the effect you want, you need to do the matching with String.prototype.match():

var arr = str.match(objReg);

The RegExp .exec() function does not behave the same way with regards to the g flag. The flag does do something with .exec() but not what .match() does.

The g modifier causes the regex object to maintain state. It tracks the index after the last match. If you wanted to use .exec(), you can use a loop, and it will automatically start searching the string at the appropriate point.

var objReg = /touch/g;
var str = "abc touch def touch";
var match = null;
var arr = [];

console.log(objReg.lastIndex);

while ((match = objReg.exec(str))) {
  arr.push(match[0]);
  console.log(objReg.lastIndex);
}

console.log(objReg.lastIndex);

console.log(arr);

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