The handler.apply()
method is a trap for a function call.
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Syntax
const p = new Proxy(target, { apply: function(target, thisArg, argumentsList) { } });
Parameters
The following parameters are passed to the apply()
method. this
is bound to the handler.
target
- The target object.
thisArg
- The
this
argument for the call. argumentsList
- The list of arguments for the call.
Return value
The apply()
method can return any value.
Description
The handler.apply()
method is a trap for a function call.
Interceptions
This trap can intercept these operations:
proxy(...args)
Function.prototype.apply()
andFunction.prototype.call()
Reflect.apply()
Invariants
If the following invariants are violated, the proxy will throw a TypeError
.
The target
must be a callable itself. That is, it must be a function object.
Examples
Trapping a function call
The following code traps a function call.
const p = new Proxy(function() {}, { apply: function(target, thisArg, argumentsList) { console.log('called: ' + argumentsList.join(', ')); return argumentsList[0] + argumentsList[1] + argumentsList[2]; } }); console.log(p(1, 2, 3)); // "called: 1, 2, 3" // 6
Specifications
Specification |
---|
ECMAScript (ECMA-262) The definition of '[[Call]]' in that specification. |
Browser compatibility
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Desktop | Mobile | Server | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
apply | Chrome Full support 49 | Edge Full support 12 | Firefox Full support 18 | IE No support No | Opera Full support 36 | Safari Full support 10 | WebView Android Full support 49 | Chrome Android Full support 49 | Firefox Android Full support 18 | Opera Android Full support 36 | Safari iOS Full support 10 | Samsung Internet Android Full support 5.0 | nodejs Full support 6.0.0 |
Legend
- Full support
- Full support
- No support
- No support