javascript中call和apply的用法樣本分析

 call和apply的用法，並利用call實現js類的繼承

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/* * 矩形 */ function Rectangle(len,width) { this.len = len; this.width = width;   } /* * 乘以 */ function multiply(a,b) { return a * b; } // 矩形執行個體 var rectangle = new Rectangle(15, 30); //求矩形面積 var proportion = multiply.call(rectangle,rectangle.len, rectangle.width); // 等價於call //var proportion = multiply.apply(rectangle,[rectangle.len, rectangle.width]);   document.write("矩形的面積是："+proportion); document.write("<br/>");   document.write("/***********************分割線********************************/<br/>");   // 實現繼承 function Persion(name) { this.name = name; this.sayHello = function () { return "hello，"+this.name; } }   function Student(name,sex,school) { Persion.call(this,name); this.sex = sex; this.school = school;   this.mySex = function () { return this.sex; } this.mySchool = function () { return this.school; } }   var stu = new Student('fengjx','男','廣西機電職業技術學院')   document.write("stu sayHello："+stu.sayHello()); document.write("<br/>"); document.write("stu sex is："+stu.mySex()); document.write("<br/>"); document.write("stu school is ："+stu.mySchool()); document.write("<br/>");

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