JavaScript Symbol.hasInstance 属性
javascriptweb developmentobject oriented programming
Symbol.hasInstance 属性用于检查构造函数是否将对象识别为其实例。
以下是 Symbol.hasInstance 属性的代码 −
示例
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>Document</title>
<style>
body {
font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
}
div {
font-size: 20px;
font-weight: 500;
}
</style>
</head>
<body>
<h1>JavaScript Symbol.hasInstance Property</h1>
<div class="sample"></div>
<button class="btn">点击此处</button>
<h3> Click on the above button to see if the above symbols are instance of array and custom() respectively</h3>
<script>
let fillEle = document.querySelector(".sample");
let ele = [1, 2, 3];
function custom() {}
var str = new custom();
fillEle.innerHTML += ele + "<br>" + custom + "<br>";
document.querySelector(".Btn").addEventListener("click", () => {
fillEle.innerHTML += Array[Symbol.hasInstance](ele) + "<br>";
fillEle.innerHTML += custom[Symbol.hasInstance](str);
});
</script>
</body>
</html>
输出
点击“CLICK HERE”按钮 −
