使用 js 簡(jiǎn)單的實(shí)現(xiàn) bind、call 、aplly代碼實(shí)例

Function.prototype._call = function(obj,...arg){
 var me = this;
 var k = Symbol("test"); //生成唯一的 key
 obj[k] = me;
 var result = obj[k](...arg);
 delete obj[k];
 return result;
}
 
Function.prototype._apply = function(obj,arg){
 var me = this;
 var k = Symbol("test"); //生成唯一的 key
 obj[k] = me;
 var result = obj[k](...arg);
 delete obj[k];
 return result;
}
Function.prototype._bind = function(obj,...arg){
 var me = this;
 return function(...args){
 var param = [...arg,...args];
 return me._apply(obj,param);
 }
}
 
 
 
var o1 = {
 info:"o1",
 print(){
 console.log(arguments)
 console.log(this.info)
 }
}
var o2 = {
 info:"o2",
 print(){
 console.log(arguments)
 console.log(this.info)
 }
}
var o3 = {
 info:"o3",
 print(){
 console.log(arguments)
 console.log(this.info)
 }
}
 
o1.print._bind(o3,11)(44,66);