非标准
该特性是非标准的,请尽量不要在生产环境中使用它!
Array.unobserve()方法用来移除Array.observe()
设置的所有观察者。
Array.unobserve(arr, callback)
arr
callback回调
Array.unobserve()
方法因为要移除观察者,所以应该在Array.observe()
调用后调用。
回调函数应该是一个函数的引用并且不能是匿名函数, 因为这个函数需要用来移除前面的观察者, 如果用匿名函数是没有用的,将不能移除任何观察者。
var arr = [1, 2, 3];
var observer = function(changes) {
console.log(changes);
}
Array.observe(arr, observer);
arr.push(4);
// [{type: "splice", object: <arr>, index: 3, removed:[], addedCount: 1}]
Array.unobserve(arr, observer);
arr.pop();
// The callback wasn't called
var persons = ['Khalid', 'Ahmed', 'Mohammed'];
Array.observe(persons, function (changes) {
console.log(changes);
});
persons.shift();
// [{type: "splice", object: <arr>, index: 0, removed: [ "Khalid" ], addedCount: 0 }]
Array.unobserve(persons, function (changes) {
console.log(changes);
});
persons.push('Abdullah');
// [{type: "splice", object: <arr>, index: 2, removed: [], addedCount: 1 }]
// The callback will always be called
Desktop | Mobile | Server | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
unobserve | Chrome No support 36 — 52 | Edge No support No | Firefox No support No | IE No support No | Opera No support No | Safari No support No | WebView Android No support No | Chrome Android No support No | Edge Mobile No support No | Firefox Android No support No | Opera Android No support No | Safari iOS No support No | Samsung Internet Android No support No | nodejs No support No |