JavaScript WeakMap delete()方法

JavaScript WeakMap delete() 方法用于从 WeakMap 对象中删除指定的元素。

语法

delete()方法由以下语法表示：

WeakMapObj.delete()

JavaScript WeakMap delete()方法示例

让我们看一个示例来确定WeakMap对象是否包含指定的元素。

<script>
var wm = new WeakMap();
var obj1 = {};
var obj2 = {};
var obj3= {};
wm.set(obj1, 'jQuery');
wm.set(obj2, 'AngularJS');
wm.set(obj3,'Bootstrap');
document.writeln("Element present before invoking delete() method: "+ wm.has(obj1)+"<br>");
wm.delete(obj1);
document.writeln("Element present after invoking delete() method: "+wm.has(obj1)); 
</script>

输出：

Element present before invoking delete() method: true
Element present after invoking delete() method: false