Excuse the petty question, but this is really nagging me. I'm following the mozilla example: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/splice Can someone explain why this doesn't work:
<body>
<p id="test">
</p>
</body>
var url = "teststring";
document.getElementById("test").innerHTML = (url.split('').splice(2,0,"teststring").join(''));
jsFiddle: https://jsfiddle.net/uyk2p437/1/
The Array#splice method returns an array containing removed elements, in your case, it would be empty and you are applying Array#join method which generates an empty string.
Use String#slice ( or String#substring) method instead :
url.slice(0, 2) + "teststring" + url.slice(2)
var url = "teststring";
document.getElementById("test").innerHTML = url.slice(0, 2) + "1" + url.slice(2);<body>
<p id="test">
</p>
</body>
substr will be better since it's a string (I don't mean in performance or anything I just meant it would make sense)! But good answer anyway!Because the return value from splice is the removed items. Not the modified array. It modifies in place
As per MDN
Return value
An array containing the deleted elements. If only one element is removed, an array of one element is returned. If no elements are removed, an empty array is returned.
var url = "teststring";
var split = url.split('');
split.splice(2,0,"teststring"); // this returns an empty array because you aren't removing anything
// but the value in split is now:
// ['t','e','t','e','s','t','s','t','r','i','n','g','s','t','s','t','r','i','n','g']
console.log(split.join('')); // gives you the expected resultOr you can use slice as in Pranav's answer, or substr or substring.
splicenotsplit. (5min already passed)!splice()doesn't return the Array you've spliced, but the array you've removed. In your caseurl.split('').slice(2,2).join('')would do exactly the same