Home >Web Front-end >JS Tutorial >Implement inheritance using call in javascript_javascript skills
Yesterday, Adan sent me an overloading example in javascript, which feels good. Although I still don’t understand how to implement it, I still posted it.
Implementing setTimeout and passing object objects
See the following code implementation Pass parameters to the function inside
call method Description in JScript Reference: Call a method of an object and replace the current object with another object. call([thisObj[,arg1[, arg2[, [,.argN]]]]]), but there is no example
Instructions in the apply method JScript reference: Apply a method of an object and replace it with another object current object. apply([thisObj[,argArray]])
In fact, the functions of these two are almost the same. What should be noted is that the arg parameter in call(thisObj[,arg1[, arg2[,)) can be a variable. The parameters in apply([thisObj[,argArray]]) are array collections.
This morning I saw another example of using call to implement inheritance. Haha... I also posted it together. This example is relatively simple. Even if it is from the shallower to the deeper
<script> <BR>var _st = window.setTimeout; <BR>window.setTimeout = function(fRef, mDelay) { <BR> if(typeof fRef == 'function'){ <BR> var argu = Array.prototype.slice.call(arguments,2); <BR> var f = (function(){ fRef.apply(null, argu); }); <BR> return _st(f, mDelay); <BR> } <BR> return _st(fRef,mDelay); <BR>} <BR>function test(x){ <BR> alert(x); <BR>} <BR>window.setTimeout(test,1000,'fason'); <BR></script><script> <br><br> function father(){//父类 <br><br> var self=this; //私有变量,子类里不会继承! <br><br> var var_private="private variable"; //私有变量 <br><br> this.var_public="public variable"; //公有变量 <br><br> <br><br> this.author="xling"; <br><br> this.test=function(msg){ //公有方法 <br><br> alert("该方法位于父类 :" + msg + "\n" + self.author); <br><br> } <br><br> <br><br> var test2=function(){ //私有方法,子类不能调用 <br><br> alert("这个方法是父类的私有方法"); <br><br> } <br><br> } <br><br> <br><br> function father2(){ <br><br> this.email="xlingFairy#hotmail.com"; <br><br> } <br><br> <br><br> function suber(){//子类 <br><br> father.call(this);//通过这一句来继承父类(father)类的可见变量及方法(this) <br><br> } <br><br> <br><br> function sun(){ <br><br> suber.call(this); <br><br> father2.call(this);//和上面的一句放在一起,實現多重繼承!爽啊! <br><br> } <br><br> <br><br> var mySuber=new suber(); <br><br> mySuber.test("参数是从子类的实例里传入的"); <br><br> //mySuber.test2(); //这一句会发生错误码,因为test2是父类的私有类 <br><br> alert("父类的私有变量,子类不能读取:" + mySuber.var_private); <br><br> alert("父类的公有变量,子类可以读取" + mySuber.var_public); <br><br> <br><br> var mySun=new sun(); <br><br> mySun.test("这个是从孙子级的实例里传入的参数"); <br><br> alert("父类的私有变量,子类不能读取:" + mySun.var_private); <br><br> alert("父类的公有变量,子类可以读取" + mySun.var_public); <br><br> alert(mySun.email); <br><br></script>