如何我在VM

從一個datepicker一個SelectedDateChanged事件綁定到命令我有一個空的代碼隱藏文件，這WPF文件（我想保持代碼隱藏空的，如果可能的話）如何我在VM

我再有這樣的視圖模型文件

using System; 
using System.Collections.ObjectModel; 
using System.Windows.Input; 
using MVVM_Test.Model; 
using MvvmFoundation.Wpf; 

namespace MVVM_Test.ViewModel 
{ 
    public class ViewModel : ObservableObject 
    { 
     private DateTime selectedDate; 
     public DateTime SelectedDate 
     { 
      get 
      { 
       return selectedDate; 
      } 
      set 
      { 
       selectedDate = value; 
       RaisePropertyChanged("SelectedDate"); 
      } 
     } 

     private DateTime startDate; 
     public DateTime StartDate 
     { 
      get { return startDate; } 
      set 
      { 
       startDate = value; 
       RaisePropertyChanged("StartDate"); 
      } 
     } 

     private DateTime endDate; 
     public DateTime EndDate 
     { 
      get { return endDate; } 
      set 
      { 
       endDate = value; 
       RaisePropertyChanged("EndDate"); 
      } 
     } 

     public ObservableCollection<Brick> SavedBricks { get; set; } 

     public ViewModel() 
     { 
      SelectedDate = DateTime.Now; 
      StartDate = new DateTime(2011, 1, 1); 
      EndDate = new DateTime(2011, 7, 31); 
      SavedBricks = new ObservableCollection<Brick>(); 
      //Brick b1 = new Brick(DateTime.Now, 50,50,50,300); 
      //SavedBricks.Add(b1); 
     } 

     public ICommand PrevHistory_cmd 
     { 
      get { return new RelayCommand(PrevHistoryExecute, PrevHistoryCanExecute); } 
     } 

     private void PrevHistoryExecute() 
     { 
      SelectedDate = SelectedDate - new TimeSpan(1, 0, 0, 0); 
     } 

     private bool PrevHistoryCanExecute() 
     { 
      if (StartDate < SelectedDate) 
       return true; 
      return false; 
     } 

     public ICommand NextHistory_cmd 
     { 
      get { return new RelayCommand(NextHistoryExecute, NextHistoryCanExecute); } 
     } 

     private void NextHistoryExecute() 
     { 
      SelectedDate = SelectedDate + new TimeSpan(1, 0, 0, 0); 
     } 

     private bool NextHistoryCanExecute() 
     { 
      if(EndDate > SelectedDate) 
       return true; 
      return false; 
     } 

     public ICommand StartStopSort_cmd 
     { 
      get { return new RelayCommand(NextHistoryExecute, NextHistoryCanExecute); } 
     } 

     private void StartStopSortExecute() 
     { 

     } 

     private bool StartStopSortCanExecute() 
     { 
      return true; 
     } 

     public ICommand DateSelectionChanged_cmd 
     { 
      get { return new RelayCommand(NextHistoryExecute, NextHistoryCanExecute); } 
     } 

     private void DateSelectionChangedExecute() 
     { 

     } 

     private bool DateSelectionChangedCanExecute() 
     { 
      return true; 
     } 
    } 
}

那麼我想SelectedDateChanged事件來執行我的公開的ICommand DateSelectionChanged_cmd，這樣我可以在我的視圖模型驗證。我試圖讓System.Windows.Interactivity工作，但當我將它作爲參考添加它不會編譯，並說它無法找到該文件，所以現在我想知道是否有任何其他方式來做到這一點，我寫的方式xml文件只是我如何猜測它會看起來的一個例子（哪種方法是錯誤的）

來源

2011-04-22 Mech0z

您不能直接將事件綁定到命令。您可以使用附加的行爲如圖所示here，但實際上你並不需要：由於結合SelectedDate是雙向的，你只需要在SelectedDate setter方法執行DateSelectionChangedExecute：

public DateTime SelectedDate 
    { 
     get 
     { 
      return selectedDate; 
     } 
     set 
     { 
      selectedDate = value; 
      RaisePropertyChanged("SelectedDate"); 
      DateSelectionChangedExecute(); 
     } 
    }

來源

2011-04-22 14:25:48

回答

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