javascript中call和apply的用法示例分析

/* * 矩形 */function Rectangle(len,width) {  this.len = len;  this.width = width; }/* * 乘以 */function multiply(a,b) {  return a * b;}// 矩形实例var rectangle = new Rectangle(15, 30);//求矩形面积var proportion = multiply.call(rectangle,rectangle.len, rectangle.width);// 等价于call//var proportion = multiply.apply(rectangle,[rectangle.len, rectangle.width]); document.write("矩形的面积是："+proportion);document.write("<br/>"); document.write("/***********************分割线********************************/<br/>"); // 实现继承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','广西机电职业技术学院') 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/>");