JavaScript的weakSet.add()方法用法介绍

2021年5月2日18:29:05 发表评论 914 次浏览

以下是示例weakSet.add()方法。

<script> function gfg() { const weakset = new WeakSet(); const object1 = {}; weakset.add(object1); document.write(weakset.has(object1)); } gfg(); </script>

输出如下:true

weakSet.add()是JavaScript中的内置函数, 用于在对象末尾添加对象弱集。通过WeakSet对象, 可以将弱保存的对象存储在集合中。

语法如下:

weakSet.add(A);

参数:它接受参数" A", 这是将添加到弱化对象的值。

返回值:它返回弱化对象。

例子:

Input: weakset.add(object1); 
Output: true

JavaScript代码显示此功能的工作方式:

代码1:

<script>
  
     //Constructing a weakset object
     const weakset = new WeakSet();
  
     //Constructing a new object object1
     const object1 = {};
     const object2 = {};
     const object3 = {};
     const object4 = {};
  
     //Adding the object1 at the end of the weakset object.
     weakset.add(object1);
     weakset.add(object2);
     weakset.add(object3);
     weakset.add(object4);
  
     //Printing either object has been added or not
     document.write(weakset.has(object1) + "<br>" );
     document.write(weakset.has(object2) + "<br>" );
     document.write(weakset.has(object3) + "<br>" );
     document.write(weakset.has(object4));
      
</script>

输出如下:

true
true
true
true

代码2:

<script>
  
     //Constructing a weakset object
     const weakset = new WeakSet();
  
     //Constructing a new object object1
     const object1 = {};
     const object2 = {};
     const object3 = {};
     const object4 = {};
  
     //Printing either object has been added or not
     document.write(weakset.has(object1) + "<br>" );
     document.write(weakset.has(object2) + "<br>" );
     document.write(weakset.has(object3) + "<br>" );
     document.write(weakset.has(object4));
      
</script>

输出如下:

false
false
false
false

这里的输出为false, 因为尚未将新创建的对象设置为weakSet()对象的末尾。

支持的浏览器:

  • 谷歌浏览器
  • IE浏览器
  • 火狐浏览器
  • 苹果Safari
  • 歌剧

木子山

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