13-apply.html

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    <title>Document</title>
    <script>
        Function.prototype.myApply = function (obj) {
            console.log('obj', obj, arguments);
            let _this = obj || window
            _this.temp = this // logName.myCall, 则这里的this就是logName函数
            if (arguments[1]) {
                // 存在入参
                let args = Array.from(arguments[1])
                _this.temp(...args) // 此时等于obj调用logName函数，函数内的this指向则是obj
            } else {
                _this.temp()
            }
            delete _this.temp
        }


        var person = {
            name: 'lxf'
        }

        function logName() {
            console.log(this.name);
        }

        logName.myApply(person, ['jack', 'mark'])
    </script>
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