Question

有一个模块在我的项目中的特定JS文件中实现，如下例

define("Company", ["exports", "Employee"], function(Employee) {
    function Company(name) {
        this.name = name;
        this.employees = [];
    };
    Company.prototype.addEmployee = function(name) {
        var employee = new Employee.Employee(name);
        this.employees.push(employee);
        employee.company = this;
    };
    exports.Company = Company;
});

现在在不同的JS文件（新模块）中我想扩展 addEmployee 方法，例如我想向它添加地址数据，是否可能？如果是的话我应该怎么做？示例将非常有用！

提前致谢！

Answer 1

如果您只想为一个实例更改此方法，那么您可以在模块中创建Company的新实例，通过添加您自己的代码覆盖实例上的addEmployee方法，而不是从原型中调用原始方法：

// create a new instance of Company
var myCompany = new Company('myCompany');
// add method 'addEmployee' to your instance, it will override original method
// you can, of course, add more arguments if you wish
myCompany.addEmployee = function(name) {
    // your code here
    // and than call the original method settings it's 'this' to 'this' of your instance, 
    // and providing appropriate arguments
    Company.prototype.addEmployee.call(this, name);
}

Answer 2

这样的事情有用吗？

//required as Company
(function(){
  var addEmployee = Company.prototype.addEmployee;
  Company.prototype.addEmployee = function(name, address){
    //assuming the original addEmployee returns the created instance
    var emp = addEmployee.call(this,name);
    //do something with address
    emp.address=address;
    return emp;//also return the created employee so it'll behave the same as the original
  }
}())

如何扩展使用原型的javascript模块

2 个答案: