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Question

Search for all instances of a string inside a string.

Answer 1

+2 A:

I don't know if there's a built in function to do it. You could do it in a simple loop though:

function allIndexes(lookIn, lookFor) {
    var indices = new Array();
    var index = 0;
    var i = 0;
    while(index = lookIn.indexOf(lookFor, index) > 0) {
        indices[i] = index;
        i++;
    }
    return indices;
}

carnold 2010-07-29 18:47:24

Answer 2

A:

You can use indexOf('searchstring', ), using the index returned 'last time round' + 1 until you get -1 back.

Will A 2010-07-29 18:48:07

Answer 3

+1 A:

Try something like:

var regexp = /abc/g;
var foo = "abc1, abc2, abc3, zxy, abc4";
var match, matches = [];

while ((match = regexp.exec(foo)) != null) {
  matches.push(match.index);
}

console.log(matches);

cic 2010-07-29 18:56:53

I forget so easily that the match object has the "index" property!

Pointy 2010-07-29 19:03:41

Thanks a lot man! regex did the trick!!

sai 2010-07-29 19:04:04

Answer 4

A:

Here's a regex way to do it:

function positions(str, text) {
  var pos = [], regex = new RegExp("(.*?)" + str, "g"), prev = 0;
  text.replace(regex, function(_, s) {
    var p = s.length + prev;
    pos.push(p);
    prev = p + str.length;
  });
  return pos;
}

Pointy 2010-07-29 18:57:48

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Search for all instances of a string inside a string.

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