如何使用OOP javascript進行此操作？

Question

我是JavaScript的新手，只是試着像PHP一樣做一些東西。 在下面的例子中，我不能使用THIS關鍵字一般調用類Screen的getMyWeekDay（）方法，我在原型函數中要做的就是調用我的“Screen”類的特定實例（即我的實例）叫做“屏幕”）哪種破壞目的有點......

我想我剛剛在設計中犯了一個新手錯誤？

//Our screen object
function Screen() {}

//update the clock element on the screen
Screen.prototype.updateClock = function(date) {
    //do some stuff
    $('#dateContainer').html(screen.getMyWeekDay(date)+' '+date);
    //Here I would prefer    $('#dateContainer').html(this.getMyWeekDay(date)+' '+date);
}

//return the day name in swedish
Screen.prototype.getMyWeekDay = function(d) {
    var d=new Date(d);
    var weekday=new Array(7);
    weekday[0]="Söndag";
    weekday[1]="Måndag";
    weekday[2]="Tisdag";
    weekday[3]="Onsdag";
    weekday[4]="Torsdag";
    weekday[5]="Fredag";
    weekday[6]="Lördag";
    var n = weekday[d.getDay()];
    return n;
}

screen = new Screen();

//use the new instance (screen) of class Screen

- 更新 -

我意識到我的問題可能超出了我分享的代碼，使用了建議的解決方案。

這是我的整個代碼，我只是試圖為您節省一些我認為不必要的閱讀...

Screen.prototype.updateClock = function() {

    var jqxhr = $.get('{{ path('getClock') }}')
      .success(function(data) { 
            time = data.substring(data.indexOf("|")+1, data.indexOf("|")+6);
            date = data.substring(0, data.indexOf("|"));

            $('#timeContainer').html(time);          

            try{
                //see if template has its own function for date rendering...
                template_date_format(getMyWeekDay(date),date);
            }
            catch(e) {
                //standard fallback if not
                $('#dateContainer').html(this.getMyWeekDay(date)+' '+date);
            }       
       })
      .error(function() {
            console.log('there was an error fetching clock data');
      });        
            setTimeout(function() {
              updateClock();
            }, 15000);          

}

Answer 1

Screen.prototype.updateClock = function() {

var oopThis = this;

var jqxhr = $.get('{{ path('getClock') }}')
    .success(function(data) { 

        // the log line below will return an object which contains the ajax calls options
        console.log(this);

        time = data.substring(data.indexOf("|")+1, data.indexOf("|")+6);
        date = data.substring(0, data.indexOf("|"));

        $('#timeContainer').html(time);          

        try {
            //see if template has its own function for date rendering...
            template_date_format(getMyWeekDay(date),date);
        } catch(e) {
            //standard fallback if not
            $('#dateContainer').html(oopThis.getMyWeekDay(date)+' '+date);
        }    
    })
    .error(function() {
        console.log('there was an error fetching clock data');
    });        

    setTimeout(function() {
        oopThis.updateClock();
    }, 15000);
}

好。 基於上面的代碼， this在ajax/get/post函數的上下文中引用包含其選項的ajax對象。

BTW，常見的慣例是做var self = this;