function Test002(name, age){

                  name,

                  age,

                  this.printInfo = function(){ //定义的公有方法

                      console.log(name, age);

                  }

              }

              let test002 = new Test002("weisheng", 32)

              test002.printInfo()   //打印 weisheng 32



              function Test003(name, age){

                  name;

                  age;

                  var printInfo = function(){

                      console.log(name, age);

                  }

              }

              let test003 = new Test003("weisheng", 32)

              test003.printInfo()   //报错，私有方法