如何以 MVVM 方式实现此 TextChanged 事件处理程序？

Question

如何以 MVVM 方式实现此事件处理程序？

我见过的其他解决方案是否在视图模型上实现了命令或属性。但是，这意味着每个文本更改事件都会变成命令执行或属性集。但是这个事件处理程序会过滤掉除用户输入之外的所有内容。您将如何使用命令或属性绑定来做到这一点？

private async void SearchBox_TextChanged(AutoSuggestBox sender, AutoSuggestBoxTextChangedEventArgs args)
{
   if (args.Reason == AutoSuggestionBoxTextChangeReason.UserInput)
   {
      await this.ViewModel.RefreshAddressSuggestions(sender.Text);    
   }
}

Answer 1

How do I implement this TextChanged event handler the MVVM way?

根据您的要求，您可以将 Text 属性与 ViewModel 绑定，并检查文本值更改以调用 RefreshAddressSuggestions 方法。

<AutoSuggestBox Text="{x:Bind SearchText, Mode=TwoWay}"> 


private string searchText;

public event PropertyChangedEventHandler PropertyChanged;
private void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
    if (PropertyChanged != null)
    {
        this.PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
    }
}
public string SearchText
{

    get { return searchText; }
    set
    {
        _passWord = value;
        this.ViewModel.RefreshAddressSuggestions(value);
        OnPropertyChanged();


    }
}

如何以 MVVM 方式实现此 TextChanged 事件处理程序？

How do I implement this TextChanged event handler the MVVM way?

c#

event-handling

mvvm

textchanged

uwp