I have some text:

```
<p>hello world. This is a test paragraph.</p>

```

I want to add an `<em>` tag at start positions and `</em>` at end positions giving us:

```
<p>
  <em>hello</em> world. This is a <em>test</em> paragraph.
</p>

```

I have a list of start and end positions

```
<lst name="offsets">
  <int name="start">0</int>
  <int name="end">5</int>
  <int name="start">22</int>
  <int name="end">27</int>
</lst>

```

Is there an easy way of doing this?

Here is how I did it (slight modification of the answer):

```
var p = doc+=" "//document.querySelector("#content"),//I added a space to the end of the document because if we try to wrap the em tags around the word we are looking for and it is at the end of the document then it gives us undefined.
    textArray = p.split('');
    //offsets = [{ start: 0, end: 5 }, { start: 22, end: 27 }];

    offsets.forEach(function (offset) {    
    textArray[offset.start] = '<em>' + textArray[offset.start];
    textArray[offset.end] = '</em>' + textArray[offset.end];
});

document.querySelector("#content").innerHTML += textArray.join('');
document.querySelector("#content").innerHTML += "<hr>";

```