The replace()
method of the DOMTokenList
interface replaces an existing token with a new token. If the first token doesn't exist, replace()
returns false
immediately, without adding the new token to the token list.
Syntax
tokenList.replace(oldToken, newToken);
Parameters
oldToken
- A
DOMString
representing the token you want to replace. newToken
- A
DOMString
representing the token you want to replaceoldToken
with.
Return value
A boolean value, which is true
if oldToken
was successfully replaced, or false
if not.
Note: In older browsers, replace()
returns void.
Examples
In the following example we retrieve the list of classes set on a <span>
element as a DOMTokenList
using Element.classList
. We then replace a token in the list, and write the list into the <span>
's Node.textContent
.
First, the HTML:
<span class="a b c"></span>
Now the JavaScript:
let span = document.querySelector("span"); let classes = span.classList; let result = classes.replace("c", "z"); console.log(result); if (result) { span.textContent = classes; } else { span.textContent = 'token not replaced successfully'; }
The output looks like this:
Polyfill
The following polyfill will add the replace method to the DOMTokenList
class. The following code will only work with IE10-11. To use with earlier versions of IE, refer to the polyfill at element.classList#Polyfill
DOMTokenList.prototype.replace = function (a, b) {
if (this.contains(a)) {
this.add(b);
this.remove(a);
return true;
}
return false;
}
Specifications
Specification | Status | Comment |
---|---|---|
DOM The definition of 'replace()' in that specification. |
Living Standard | Initial definition |
Browser compatibility
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
replace | Chrome Full support 61 | Edge Full support 17 | Firefox Full support 49 | IE No support No | Opera Full support 48 | Safari Full support 10.1 | WebView Android Full support 61 | Chrome Android Full support 61 | Firefox Android Full support 49 | Opera Android Full support 45 | Safari iOS Full support 10.3 | Samsung Internet Android Full support 8.0 |
return() 's value is a boolean, not void as it used to be. | Chrome Full support 67 | Edge Full support 18 | Firefox Full support 61 | IE No support No | Opera Full support 54 | Safari Full support 12 | WebView Android Full support 67 | Chrome Android Full support 67 | Firefox Android Full support 61 | Opera Android Full support 48 | Safari iOS Full support 12 | Samsung Internet Android Full support 9.0 |
Legend
- Full support
- Full support
- No support
- No support