Question

我不确定如何像在Java中那样创建对象。现在，我在CalendarDate.js文件中具有以下代码，并且有信心使用相同的实例。我将此文件导入了main.js文件，并按以下方式进行处理： var selectedDay = CalendarDate.SELECTED_DAY;

但是，如果我要尝试创建一个新对象（我很确定，它不能像这样工作，虽然可能是JavaScript有所不同），如下所示：

 var secondDay = CalendarDate.SELECTED_DAY;

我正在使用与selectedDay相同的参考。不知道，如果这在javascript中有意义，但是，我需要一些类似的东西： var selectedDay = new CalendarDate（）甚至是这样的->

var selectedDay = new CalendarDate("2018-10-21") //or like this:
var selectedDay  = new CalendarDate(2018,10,21).

所以也许我想使用级联构造函数。

希望您能理解我的观点，如果有人可以给我提示如何更改CalendarDate.js文件以便以预期的方式使用它，请随时回答:)

[如果有任何初学者（例如我是一个人）需要这样的东西，只需擦一下它即可：）]

//CalendarDate.js
var SELECTED_DAY =  {
    dateString: "",
    day: "",
    month: "",
    year: "",

    statusStr: "",
    'setDate': function(dateStr){
        this.dateString = dateStr;
        if(this.hasRightFormat()){
            this.day = this.dateString.split("-")[2];
            this.month = this.dateString.split("-")[1];
            this.year = this.dateString.split("-")[0];
        }else{
            this.dateString = "";
            this.day = "";
            this.month = "";
            this.year = "";
        }
    },

    'hasRightFormat': function(){
        this.statusStr = "";
        if(this.dateString !== "" || this.dateString !== "undefined" ){
            this.statusStr += "it's not undefined (Y)\n";
            if(this.dateString.split("-").length == 3){
                this.statusStr+= "It has a split-length of 3 (Y)\n";
                if(this.dateString.split("-")[0].length != 4){
                    this.statusStr+= "WRONGYEARFORMAT? (N)\n";
                    return false;
                }
                if(this.dateString.split("-")[1].length != 2 || this.dateString.split("-")[2].length != 2){
                    this.statusStr+= "IT HAS EITHER A WRONG DAY OR MONTH FORMAT\n";
                    return false;
                }
                //right format
                return true;
            }
        }
        // return false;
        return false;
    },
    'getStatus': function(){
        return this.statusStr;
    },
    'test': function(){
        return "TESTVALUE";
    },
    'day': function(){
            return this.date.split("-")[2];
            /*if(this.hasRightFormat()){
                return this.date.split("-")[2];
            }
            return "undefined";*/
    },
    'month': function(){
        if(this.hasRightFormat()){
            return this.date.split("-")[1];
        }
        return null;
    },
    'year': function(){
        if(this.hasRightFormat()){
            return this.date.split("-")[0];
        }
        return null;
    },
};

module.exports = {SELECTED_DAY};

现在-关于@ssougnez的建议-我已经尝试解决此问题，如果我尝试像var selectedDay = new CalendarDate（“ 2018-01-01”）那样访问它，则会出现此错误：“ TypeError：Object is不是构造函数（评估'new _CalendarDate2.default（）'）“

function CalendarDate(dateStr){
    this.dateString = dateStr;
    this.day = this.day();
    this.month = this.month();
    this.year = this.year();
}
this.hasRightFormat = function(){
    this.statusStr = "";
    if(this.dateString !== "" || this.dateString !== "undefined" ){
        this.statusStr += "it's not undefined (Y)\n";
        if(this.dateString.split("-").length == 3){
            this.statusStr+= "It has a split-length of 3 (Y)\n";
            if(this.dateString.split("-")[0].length != 4){
                this.statusStr+= "WRONGYEARFORMAT? (N)\n";
                return false;
            }
            if(this.dateString.split("-")[1].length != 2 || this.dateString.split("-")[2].length != 2){
                this.statusStr+= "IT HAS EITHER A WRONG DAY OR MONTH FORMAT\n";
                return false;
            }
            //right format
            return true;
        }
    }
    // return false;
    return false;
}

this.setDate = function(dateString){
    cache = this.dateString;
    this.dateString = dateString;
    if (this.hasRightFormat()){
        this.day = this.day();
        this.month = this.month();
        this.year = this.year();
    }
}
this.day =  function(){
        return this.dateString.split("-")[2];
        if(this.hasRightFormat()){
            return this.date.split("-")[2];
        }
        return null;
}
this.month = function(){
    if(this.hasRightFormat()){
        return this.dateString.split("-")[1];
    }
    return null;
}
this.year = function(){
    if(this.hasRightFormat()){
        return this.dateString.split("-")[0];
    }
    return null;
}

Javascript创建自己的对象

0 个答案: