Function.prototype.myBind = function(context) {if (typeof this !== 'function') {return}const args = [...arguments].slice(1)const fn = thisreturn function Fn() {// 判断函数作为构造函数的情况,这个时候需要传入当前的函数的this给apply调用,其余情况都传入指定的上下文对象const target = this instanceof Fn ? this : contextreturn fn.apply(target, args.concat([...arguments]))}
}function setName(name) {this.name = name
}const obj = {age: 1
}
const setName1 = setName.bind(obj)
setName1('test')
console.log('正确结果', obj)
const setName2 = setName.myBind(obj)
setName1('miome')
console.log('正确结果', obj)