Question

我正在使用JavaScript来处理名称空间，类，继承和模式责任链，但它不起作用 - 我尝试过this tutorial，但是当我尝试实现命名空间和超级构造函数，它不起作用，所以我假设我错过了什么。

我有不同文件中的类，我使用相同的命名空间。我有一个班级Constraint.js：

var Namespace = Namespace || {};

//parent class
Namespace.Constraint = (function() {

    //How can I do a constructor with the namespace?
    /**
        function Namespace.Constraint(value, succesor, type) {
            this.value = value;
            this.succesor = succesor;
            this.type = type;
            this.noTopic = "UNDEFINED";
        }
    */

    Namespace.Constraint.prototype.handle = function() {
        if (this.has()) {
            return this.succesor.handle();
        }
    }
    Namespace.Constraint.prototype.has = function() {
        return this.type != this.noTopic;
    }
    return Constraint;
})();

接下来是具有继承的类，它位于另一个文件StringConstraint.js中：

 var Namespace = Namespace ||{};

 Namespace.StringConstraint = (function(_super){

     /**Constructor child*/
     /*
     Namespace.StringConstraint = function(value, succesor) {
         _super.call(value, succesor, "string");
         How to call the constructor of the parent?
     }
     */

     Namespace.StringConstraint.prototype.handle = function() {

         if (this.has()) {
            return "type=text";
         }
         else{

            /* Is this the correct way to call a method of the parent? */
            _super.prototype.handle.call(this);
         }
     }

     Namespace.StringConstraint.prototype.has=function(){
        /* this.type is a value of parent class. Is this the correct way
           to call it? Maybe I should use _super.type?

        */
        return this.type === "string";
     }
     return Namespace.StringConstraint;

 })(Namespace.Constraint); //Reference to parent, but is it fine with the namespace?

班级BuilderConstraint.js：

 var Namespace = Namespace ||{};

 Namespace.BuilderConstraint = (function() {
     this.constraints = new Array();

        Namespace.BuilderConstraint.prototype.add = function( constraint ) {
            this.constraints.push(constraint);
        }
        Namespace.BuilderConstraint.prototype.applyConstraint  = function(callback) {
        for (constraint in this.constraints) {

            //How to ensure that class is Constraint?
            //Because I could get object [index], has not a method handle.
            callback(constraint.handle());
        }
    }
 })();

最后是文件app.js，即我的主要文件：

 $(function() {
     var value = "string";
     var builderConstraint = new Namespace.BuilderConstaint();
     var stringConstraint = new Namespace.StringConstraint(value,null);
     builderConstraint.add(stringConstraint);

     builderConstraint.applyConstraint(function(out) {
         console.log(out);
     })
 });

我希望不要太尴尬，但我很困惑。

所以，我的问题是：

如何在不同的JavaScript文件中正确使用命名空间？
如何在不覆盖命名空间的情况下添加类？
如何使用命名空间编写类的构造函数？
如何在中使用类父类的构造函数班级孩子的构造者？
将继承类与命名空间一起使用的正确方法是什么？
如何在子类中正确使用父属性？

这是一个类约束（父类）：

/**
 *  Clase padre
 */

var XMLFormBuilder  = XMLFormBuilder  || {};

XMLFormBuilder.Constraint= (function()
{
    function Constraint( value, succesor, type ) {
    this.value = value || "UNDEFINED";
    this.succesor = succesor || null;
    this.type = type || "UNDEFINED";
    this.noTopic = "UNDEFINED";
};

Constraint.prototype.handle = function()
{
    if (typeof null != this.succesor ) {
    {
       return this.succesor.handle();
    }
};

Constraint.prototype.has = function()
{
    return this.type != this.noTopic;
};

return Constraint;

})(); // <-- **Here, there is a trouble.**

班级StringConstraint（儿童班）：

/**Child class*/
var XMLFormBuilder = XMLFormBuilder || {};

XMLFormBuilder.StringConstraint=(function(_super)
{
    function StringConstraint(value, succesor)
    {
        this.value = value || "UNDEFINED";
        this.succesor = succesor || null;
        _super.call( this.value, this.succesor, "cadena" );

       /**
        * How to I do to use the constructor of class parent in the constructor of class child?
        * Aquí hay un error, porque no se como llamar correctamente al contructor
        * de la clase padre o como lo sugiere el error que _super no esta definido.
        * Cannot call method 'call' of undefined;
       */

    };
    /* Aquí se genera un error si activo la sobreescritura del prototipo:
        Uncaught SyntaxError: Unexpected token ) /entidad/js/Constraint.js:28
        Uncaught TypeError: undefined is not a function StringConstraint.js:16
        Uncaught TypeError: undefined is not a function

        There is a trouble, because I can't overwrite the prototype
    */
    //StringConstraint.prototype = new _super;

    StringConstraint.prototype.handle=function()
    {
        if(this.has())
            return "type='text'";
        else
           return _super.handle();
    };

    StringConstraint.prototype.has = function()
    {
        return this.type === "cadena";
    }

    return StringConstraint;

    })(XMLFormBuilder.Constraint);

这是一个班级BuilderConstraint：

var XMLFormBuilder = XMLFormBuilder || {};

XMLFormBuilder.BuilderConstraint = (function()
{
    function BuilderConstraint() {
        this.constraints = new Array();
    }
    BuilderConstraint.prototype.add = function(constraint){
        this.constraints.push(constraint);
    }

    BuilderConstraint.prototype.applyContraints = function()
    {
        var out = "";
        /*
            this.constraints.forEach(function(object){
                out += object.handle();
            });
        */

        for (var index in this.constraints) {
            var constraint = this.constraints[index];
            /* Aquí se me presenta un error, ya que no me
            *  reconoce el método handle de los objetos tipo Constraint
            *  que agrege al array
            */
            out+= constraint.handle();
        }
        return out;
    }
    return BuilderConstraint;
})();

这是app.js：

$(function()
{
    var value = "cadena";
    var stringConstraint = new XMLFormBuilder.StringConstraint(value);
    var builderConstraint = new XMLFormBuilder.BuilderConstraint();
    builderConstraint.add(stringConstraint);
    console.log(builderConstraint.applyContraints());
});

/**
* This is the summary the problems:
*   Uncaught SyntaxError: Unexpected token ) Constraint.js:28
*   Uncaught TypeError: Cannot call method 'call' of undefined
*/

您可以在此处查看代码：https://gist.github.com/cristianchaparroa/f4ace75aeb8cff04181a

Answer 1

您应该执行以下操作：

Namespace.Constraint = (function(){

   // Create a function in the current execution context
   function Constraint( value, succesor, type ){
      this.value = value;
      this.succesor = succesor;
      this.type = type;
      this.noTopic = "UNDEFINED";

  }

  // Assign to the above function's prototype
  Constraint.prototype.handle =function(){
     if( this.has() ){
         return this.succesor.handle();
      }
  }

  Constraint.prototype.has = function(){
     return this.type != this.noTopic;
  }

  // Return the function so it is assigned to Namespace.Constraint
  return Constraint;

})();

在立即调用的函数表达式（IIFE）中，您可以调用函数 Constraint 任何您喜欢的函数，因为该函数的名称是本地的。返回值是对该函数对象的引用，并分配给 Namespace.Constraint 。

命名空间和继承：具有JavaScript责任链的超级构造函数

1 个答案: