主幹模型作用域問題與骨幹驗證自定義功能

Question

我在我的Backbone模型中有一個作用域問題。我正在嘗試引用Backbone.Validation對象中的模型函數。

也就是說，我不能從validation對象/圖中訪問模型功能validateDob：

Backbone.Model.extend({ 

    validation: { 
     firstname: { required: true, msg: _('First Name is required').translate() } 
    , dobday: this.validateDob // this. refers to the immediate object {} 
    , dobmonth: validateDob  // undefined function 
    , dobyear: this.validateDob // How can I access the function validateDob? 
    } 

, validateDob: function(value) { 
     var selDay = $('select[name="dobday"] option:selected').val(); 
     var selMonth = $('select[name="dobmonth"] option:selected').val(); 
     var selYear = $('select[name="dobyear"] option:selected').val(); 

     if (!Utils.isAdult(selDay, selMonth, selYear)) 
      return _('You have to be at least 18 years old.').translate(); 
    } 
}); 

任何意見，我該怎麼設置呢？

Answer 1

你可以試試這個

Backbone.Model.extend({ 
    validation: { 
     firstname: { required: true, msg: _('First Name is required').translate() } 
    }, 
    initialize:function() { 
     this.validation.dobyear= this.validateDob; 
     //you can other props similarly 
    }, 
    validateDob: function(value) { 
     var selDay = $('select[name="dobday"] option:selected').val(); 
     var selMonth = $('select[name="dobmonth"] option:selected').val(); 
     var selYear = $('select[name="dobyear"] option:selected').val(); 

     if (!Utils.isAdult(selDay, selMonth, selYear)) 
      return _('You have to be at least 18 years old.').translate(); 
    } 
}); 

Answer 2

看你的代碼，validateDob不需要訪問實例，因此，你可以讓一個名爲功能如下：

function validateDob(value) { 
    var selDay = $('select[name="dobday"] option:selected').val(); 
    var selMonth = $('select[name="dobmonth"] option:selected').val(); 
    var selYear = $('select[name="dobyear"] option:selected').val(); 

    if (!Utils.isAdult(selDay, selMonth, selYear)) 
    return _('You have to be at least 18 years old.').translate(); 
} 

Backbone.Model.extend({ 
    validation: { 
    firstname: { 
     required: true, 
     msg: _('First Name is required').translate() 
    }, 
    dobday: validateDob, 
    dobmonth: validateDob, 
    dobyear: validateDob 
    }, 
    validateDob: validateDob 
}); 

---

但是，使用全局選擇器直接從DOM訪問值不是推薦的做法。您應該使用選擇器將這些值設置爲模態屬性，其範圍是查看元素。

在這種情況下，假設你使用backbone.validation插件，您可以定義返回驗證配置類似的功能：

Backbone.Model.extend({ 
    validation: function() { 
    return { 
     firstname: { 
     required: true, 
     msg: _('First Name is required').translate() 
     }, 
     dobday: this.validateDob, // this should be modal instance now 
     dobmonth: this.validateDob, 
     dobyear: this.validateDob 
    } 
    }, 
    validateDob: function(value) { 
    // Now context should be the modal instance so you can do this.get('prop') 
    var selDay = $('select[name="dobday"] option:selected').val(); 
    var selMonth = $('select[name="dobmonth"] option:selected').val(); 
    var selYear = $('select[name="dobyear"] option:selected').val(); 

    if (!Utils.isAdult(selDay, selMonth, selYear)) 
     return _('You have to be at least 18 years old.').translate(); 
    } 
});