handwriting-algorithm/08bind.html at master · ustcfury/handwriting-algorithm · GitHub

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<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <script>
        // bind 函数实现
        Function.prototype.myBind = function (context) {
            // 判断调用对象是否为函数
            if (typeof this !== "function") {
                throw new TypeError("Error");
            }
            // 获取参数
            var args = [...arguments].slice(1),
                fn = this;
            return function Fn() {
                // 根据调用方式，传入不同绑定值
                return fn.apply(
                    this instanceof Fn ? this : context,
                    args.concat(...arguments)
                );
            };
        };
    </script>
</body>

</html>