Примеры для jQuery.proxy()


Change the context of functions bound to a click handler using the "function, context" signature. Unbind the first handler after first click.

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<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>jQuery.proxy demo</title>
<script src="https://code.jquery.com/jquery-1.10.2.js"></script>
</head>
<body>
<p><button type="button" id="test">Test</button></p>
<div id="log"></div>
<script>
var me = {
type: "zombie",
test: function( event ) {
// Without proxy, `this` would refer to the event target
// use event.target to reference that element.
var element = event.target;
$( element ).css( "background-color", "red" );
// With proxy, `this` refers to the me object encapsulating
// this function.
$( "#log" ).append( "Hello " + this.type + "<br>" );
$( "#test" ).off( "click", this.test );
}
};
var you = {
type: "person",
test: function( event ) {
$( "#log" ).append( this.type + " " );
}
};
// Execute you.test() in the context of the `you` object
// no matter where it is called
// i.e. the `this` keyword will refer to `you`
var youClick = $.proxy( you.test, you );
// attach click handlers to #test
$( "#test" )
// this === "zombie"; handler unbound after first click
.on( "click", $.proxy( me.test, me ) )
// this === "person"
.on( "click", youClick )
// this === "zombie"
.on( "click", $.proxy( you.test, me ) )
// this === "<button> element"
.on( "click", you.test );
</script>
</body>
</html>

Демонстрация:

Enforce the context of the function using the "context, function name" signature. Unbind the handler after first click.

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<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>jQuery.proxy demo</title>
<script src="https://code.jquery.com/jquery-1.10.2.js"></script>
</head>
<body>
<p><button id="test">Test</button></p>
<p id="log"></p>
<script>
var obj = {
name: "John",
test: function() {
$( "#log" ).append( this.name );
$( "#test" ).off( "click", obj.test );
}
};
$( "#test" ).on( "click", jQuery.proxy( obj, "test" ) );
</script>
</body>
</html>

Демонстрация:

Change the context of a function bound to the click handler,

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<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>jQuery.proxy demo</title>
<script src="https://code.jquery.com/jquery-1.10.2.js"></script>
</head>
<body>
<p><button type="button" id="test">Test</button></p>
<div id="log"></div>
<script>
var me = {
// I'm a dog
type: "dog",
// Note that event comes *after* one and two
test: function( one, two, event ) {
$( "#log" )
// `one` maps to `you`, the 1st additional
// argument in the $.proxy function call
.append( "<h3>Hello " + one.type + ":</h3>" )
// The `this` keyword refers to `me`
// (the 2nd, context, argument of $.proxy)
.append( "I am a " + this.type + ", " )
// `two` maps to `they`, the 2nd additional
// argument in the $.proxy function call
.append( "and they are " + two.type + ".<br>" )
// The event type is "click"
.append( "Thanks for " + event.type + "ing." )
// The clicked element is `event.target`,
// and its type is "button"
.append( "the " + event.target.type + "." );
}
};
var you = { type: "cat" };
var they = { type: "fish" };
// Set up handler to execute me.test() in the context
// of `me`, with `you` and `they` as additional arguments
var proxy = $.proxy( me.test, me, you, they );
$( "#test" )
.on( "click", proxy );
</script>
</body>
</html>

Демонстрация: