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javascripthtmlstringparsingdom

Why am I getting a ParseError?

I am trying to use DOMParser method .parseFromString to convert strings I have in array containing HTML in to DOM elements.

Some of the strings are getting the following parse errors and I can't figure out why.

This is the loop I'm using to parse the strings and create the DOM elements (thanks to this stackoverflow post: Converting HTML string into DOM elements?)

var x = 0;
while (x < stringsArray.length) {
  var parser = new DOMParser();
  var doc = parser.parseFromString(stringsArray[x].html, "text/xml");
  outputDOMElements[x] = doc.firstChild;
  x++;
}

This is an example of a string that is successfully parsed:

"<div class="instagrampost"><span>Siamak Amini</span><p>#USA</p><span>Posted 1 month ago</span><a href="https://instagram.com/p/3zG3kDGeE8/"><img src="https://scontent.cdninstagram.com/hphotos-xaf1/t51.2885-15/s320x320/e15/11377935_1114448771906000_731563461_n.jpg" /></a></div>"

This is an example of a string that has a parse error:

"<div class="user">
  <a  href="https://twitter.com/theclarkofben" aria-label="Ben Clark (screen name: theclarkofben)" data-scribe="element:user_link" target="_blank">
    <img  alt="" src="https://pbs.twimg.com/profile_images/1877162520/199389_10150123771869463_502259462_6247107_944624_n_normal.jpg" data-src-2x="https://pbs.twimg.com/profile_images/1877162520/199389_10150123771869463_502259462_6247107_944624_n_bigger.jpg" data-scribe="element:avatar">
    <span >

      <span  data-scribe="element:name">Ben Clark</span>
    </span>
    <span   data-scribe="element:screen_name">@theclarkofben</span>

  </a>
</div><p class="tweet">Just testing out the Twitter feed I just made. <a href="https://twitter.com/hashtag/halogenpeanut?src=hash"     data-scribe="element:hashtag" target="_blank">#halogenpeanut</a> <a href="http://t.co/WtoznYSUGS"  data-pre-embedded="true"  data-scribe="" target="_blank">pic.twitter.com/WtoznYSUGS</a></p><p class="timePosted"><a href="https://twitter.com/theclarkofben/status/611514122509922304">Posted on 18 Jun</a></p><div class="media"><img src="https://pbs.twimg.com/media/CHyI2rqWEAAJRN-.jpg:large" alt="Image from tweet" /></div>"

The parse error for the above string states: error on line 10 at column 7: Opening and ending tag mismatch: img line 0 and a

And here is the full output from .parseFromString for the above string:

<div class="user"><parsererror xmlns="http://www.w3.org/1999/xhtml" style="display: block; white-space: pre; border: 2px solid #c77; padding: 0 1em 0 1em; margin: 1em; background-color: #fdd; color: black"><h3>This page contains the following errors:</h3><div style="font-family:monospace;font-size:12px">error on line 10 at column 7: Opening and ending tag mismatch: img line 0 and a
</div><h3>Below is a rendering of the page up to the first error.</h3></parsererror>
  <a href="https://twitter.com/theclarkofben" aria-label="Ben Clark (screen name: theclarkofben)" data-scribe="element:user_link" target="_blank">
    <img alt="" src="https://pbs.twimg.com/profile_images/1877162520/199389_10150123771869463_502259462_6247107_944624_n_normal.jpg" data-src-2x="https://pbs.twimg.com/profile_images/1877162520/199389_10150123771869463_502259462_6247107_944624_n_bigger.jpg" data-scribe="element:avatar">
    <span>

      <span data-scribe="element:name">Ben Clark</span>
    </span>
    <span data-scribe="element:screen_name">@theclarkofben</span></img></a></div>

Is anyone able to help me identify the cause and fix? Could it be the whitespace in the HTML string perhaps?

Solution

  • You have problems with quotings, you are using double quotes within the dom elements variables

    var x = "<div class="instagrampost"> .... is wrong the quotes of the html shall be single, besides, the dom elements shall not have spaces, in order to fit in a variable...

    Use doc.body.innerHTML to set the parsed html to the div obtained, you do not need a loop, also use "text/html" and not "text/xml" when passing the content type to the parser.

    below is a working example.

    var html = "<div class='user'><a  href='https://twitter.com/theclarkofben' aria-label='Ben Clark (screen name: theclarkofben)' data-scribe='element:user_link' target='_blank'><img  alt='' src='https://pbs.twimg.com/profile_images/1877162520/199389_10150123771869463_502259462_6247107_944624_n_normal.jpg' data-src-2x='https://pbs.twimg.com/profile_images/1877162520/199389_10150123771869463_502259462_6247107_944624_n_bigger.jpg' data-scribe='element:avatar'/><span><span  data-scribe='element:name'>Ben Clark</span></span><span   data-scribe='element:screen_name'>@theclarkofben</span></a></div><p class='tweet'>Just testing out the Twitter feed I just made. <a href='https://twitter.com/hashtag/halogenpeanut?src=hash'     data-scribe='element:hashtag' target='_blank'>#halogenpeanut</a> <a href='http://t.co/WtoznYSUGS'  data-pre-embedded='true'  data-scribe='' target='_blank'>pic.twitter.com/WtoznYSUGS</a></p><p class='timePosted'><a href='https://twitter.com/theclarkofben/status/611514122509922304'>Posted on 18 Jun</a></p><div class='media'><img src='https://pbs.twimg.com/media/CHyI2rqWEAAJRN-.jpg:large'alt='Image from tweet' /></div>";

parser = new DOMParser();
doc = parser.parseFromString(html, "text/html");
document.getElementById("parsedHtml").innerHTML = doc.body.innerHTML;
    <div id="parsedHtml"></div>