Script tag in JavaScript string

Question

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Answer 1

What happens?

The browser HTML parser will see the </script> within the string and it will interpret it as the end of the script element.

Look at the syntax coloring of this example:

<script>
var test = 'foo... </script> bar.....';
</script>

Note that the word bar is being treated as text content outside of the script element...

A commonly used technique is to use the concatenation operator:

var test = '...... </scr'+'ipt>......';