Question

Using Javascript, I want to take the content of a string and wrap every single word with a set of <span> tags. Each span tag will have a unique ID attribute that I’ll generate. If a word is already encased in a span tag with an id, leave it alone. If it has a span tag without an id, I need to put an id in the span.

So, the following:

this is <b>a</b> <span>bunch</span> of <span id="aopksd"><i>text</i></span>

Becomes:

<span id="dwdkwkd">this</span> <span id="zdkdokw">is</span> <span id="rrrsass"><b>a</b></span> <span id="lwokdw">bunch</span> <span id="poeokf">of</span> <span id="aopksd"><i>text</i></span>

Ideas on the best way to accomplish this? I’m doing it server-side in node.js. I prefer a non-jquery method.

EDIT:
The id is something I will generate on the server. I just used placeholder fake ids for now. I will use my own globally unique id.

Answer 1

You can try this, but you might have to inspect the parameter a if you want to make a special treatment for your word already in html tag :

var str = "Bonjour, je m'appelle Francis et je suis le plus bel homme du monde​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​";
var regex = /\S+/g;

var id = 0;

var result = str.replace(regex, function(a) {
    return "<span id=" + (++id) + ">" + a + "</span>";
});​​​​​​​​​​

alert(result);

live demo : http://jsfiddle.net/NtNtj/

EDIT: If you don’t want to overwrite existing ID, you can try this

var str = "Bonjour, je m'appelle <b>Francis</b> et <span id=\"existing\">je</span> suis le plus bel homme du monde";
var regex = /(<.+?<\/.+?>|\S+)/g;

var id = 0;

var result = str.replace(regex, function(a) {

    var m = (/<(\w+)([^>]*)>([^<]*)<\/\w+>/).exec(a);

    if (m !== null && m[1] === "span" && m[2].test(/id=/)) 
        return a;

    return "<span id=" + (++id) + ">" + a + "</span>";
});

console.log(result);

http://jsfiddle.net/NtNtj/8/

EDIT: If you can have multiple word in a tag like and you still want to wrap each word in between, you can call recursively the replace function with the value inside the tag as so :

var str = "Bonjour, <b>je m'appelle Francis</b> et <span id=\"existing\">je</span> suis le plus bel homme du monde";
var regex = /(<.+?<\/.+?>|\S+)/g;

var id = 0;

var result = str.replace(regex, function(a) {

    var m = (/<(\w+)([^>]*)>([^<]*)<\/\w+>/).exec(a);

    if (m !== null && m[1] === "span" && m[2].test(/id=/)) 
        return a;

    if (m !== null)
        return "<" + m[1] + m[2] + ">" + m[3].replace(regex, arguments.callee) + "</" + m[1] + ">";

    return "<span id=" + (++id) + ">" + a + "</span>";
});

console.log(result);

live demo: http://jsfiddle.net/francisfortier/NtNtj/9/