​x
 
<!DOCTYPE html>
<html>
<body>
​
<h1>JavaScript Map.delete() 方法</h1>
​
<p>Map.delete() 从 Map 中删除指定元素</p>
​
<p>1. Map.delete() 前的元素</p>
<pre id="before"></pre>
<br />
<p>2. Map.delete() 后的元素</p>
<pre id="after"></pre>
​
<script>
function stringify(mapObj)
{
  var mapString = "Map对象一共有 " + mapObj.size + "个元素<br />";
  mapObj.forEach( function( element , key ){
      mapString += JSON.stringify(key) + ":" + element + "<br />";
  });
  return mapString;
}
​
​
// 创建对象
const apples = {name: 'Apples'};
const bananas = {name: 'Bananas'};
const oranges = {name: 'Oranges'};
​
// 创建新的 Map
const fruits = new Map();
​
// Add new Elements to the Map
fruits.set(apples, 500);
fruits.set(bananas, 300);
fruits.set(oranges, 200);
​
​
​
document.getElementById("before").innerHTML = stringify(fruits);
// 删除元素
fruits.delete(apples);
//
document.getElementById("after").innerHTML = stringify(fruits);
</script>
​
</body>
</html>