new _instanceof(obj, type){
const baseType = ['string', 'number','boolean','undefined','symbol'];
//基础类型返回false
if(baseType.includes(typeof(obj)) || obj === null) { return false };
let objP = obj.__proto__;
let typeP = type.prototype;
//判断obj的原型链是否和type原型相等
while(true){
if(objP === null){
return false
}
if(objP === typeP){
return true
}
objP = objP.__proto__
}
}
JavaScript原理——模拟instanceof
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转载自blog.csdn.net/baidu_38798835/article/details/108567604
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