JS search a string or html tag inside a string even if the searched term is not joined together

Question

I have a code editor on my site, and after the user runs the code, I want to validate if the code is correct.

For example, if the user writes the following code:

<p>Some text</p>

I want to validate if the code contains a <p> tag.

What I tried :

if(language == "HTML"){
    if (html_code.includes(expected)) {
        alert('right!');
    }
    else {
       alert("wrong");
    }
}

But it only works if the user types nothing between the <p> tag.

So how can I find if the code includes certain tags ?

Does this answer your question? [Check if a string is html or not](https://stackoverflow.com/questions/15458876/check-if-a-string-is-html-or-not) — Vinay, Jul 12 '20 at 05:33
@Viney sorry, but no this answer checks if the string is formatted as HTML, I'm trying to check if a certain HTML element exists in the code, such as — עילאי אלמלם, Jul 12 '20 at 06:02
@hev1 for example
hello world
will return true, but "Hello world" will return false Just trying to check if there's a
tag for example. — עילאי אלמלם, Jul 12 '20 at 06:04

score 0 · Answer 1 · answered Jul 12 '20 at 04:45

0

var x = document.getElementById(“myId”).value;
if (x.includes(“html”) && x.includes(“ ”) == true) {
    alert(“html tag added”)
} else {
    alert(“that tag does not exist”)
}

answered Jul 12 '20 at 04:45

That's not exactly what i need. i need to check if the user code contains a
tag for example
– עילאי אלמלם Jul 12 '20 at 06:00

score 0 · Answer 2 · answered Jul 12 '20 at 10:04

try :

var myHtml = 'Aenean lacinia bibendum <a href="/life">life</a> sed consectetur. <a href="/work">Work</a> quis risus eget urna mollis ornare <a href="/about">about</a> leo.';

var result = myHtml.search(/<\s*a[^>]*>(.*?)<\s*\/\s*a>/g);
if (result >-1) {
    alert('right!');
} else {
     alert("wrong");
}

you can replace "a" with other tag name like "p"

Vinay · Accepted Answer · 2020-07-12T12:43:04.747

Use DOMParser to make the raw HTML string into a Document object it's similar to the DOM tree normally the browser forms while parsing the HTML code

function isElementPresent(htmlContent, tag) {
  var tagFound = false;

  var parser = new DOMParser();
  var parsedHtml = parser.parseFromString(htmlContent, 'text/html'); //mimeType of html is text/html
  var listEls = parsedHtml.all

  //all property is [HTMLCollection] holding all the elements (nested or otherwise) that are in the DOM tree

  for (var i = 0; i < listEls.length; i++) {
    if (listEls[i].tagName.toLowerCase() == tag) {
      tagFound = true;
    }
  }
  return tagFound;
}


htmlContent = `<div>

            <p><b>Demo</b></p>
            <div><h2>Hello</h2></div>

          </div>`;

alert( isElementPresent(htmlContent, 'p')     ) //true
alert( isElementPresent(htmlContent, 'audio') ) //false

Thank you so much! – עילאי אלמלם Jul 14 '20 at 18:34 — עילאי אלמלם, Jul 14 '20 at 18:34

JS search a string or html tag inside a string even if the searched term is not joined together

3 Answers3