Siverlight异步数据验证二

本文介绍的是DataAnnotation验证机制,利用RIA service提供的验证机制,

需要引入名称空间:

using System.ComponentModel.DataAnnotations;

本文以填写用户名和密码为例简单说明必填验证的方法.

验证类如下:

 1         private string _userName;
 2         [Required(ErrorMessage = "必填选项")]
 3         public string UserName
 4         {
 5             get { return _userName; }
 6             set
 7             {
 8                 if (_userName!=value)
 9                 {
10                     //_userName = value;
11                     //NotifyPropertyChanged("UserName");
12 
13                     var tmpValidator = new ValidationContext(this, null, null);
14                     tmpValidator.MemberName = "UserName";
15                     Validator.ValidateProperty(value, tmpValidator);
16                     _userName = value; 
17 
18                 }
1920 
21             }
22         }

客户端设置如下:

第一步引入:

xmlns:local="clr-namespace:SilverlightApplication2"

第二步

<local:User x:Key="userDataContext"/>

第三步绑定数据源

         <TextBox Grid.Column="1" Height="30" HorizontalAlignment="Left" Margin="28,57,0,0" Name="textBox1" DataContext="{Binding Source={StaticResource userDataContext}}" Text="{Binding UserName,Mode=TwoWay,NotifyOnValidationError=True,ValidatesOnExceptions=True}" VerticalAlignment="Top" Width="158" />
2         <TextBox Height="30" HorizontalAlignment="Left" Margin="28,55,0,0" Name="textBox2"  DataContext="{Binding Source={StaticResource userDataContext}}" Text="{Binding Password,Mode=TwoWay,NotifyOnValidationError=True,ValidatesOnExceptions=True}" VerticalAlignment="Top" Width="158" Grid.Column="1" Grid.Row="1" />

第四步,捕获

 1         private void LayoutRoot_BindingValidationError(object sender, ValidationErrorEventArgs e)
 2         {
 3             if (e.Action == ValidationErrorEventAction.Added)
 4             {
 5                 (e.OriginalSource as Control).Background = new SolidColorBrush(Colors.Yellow);
 6                 tbMessage.Text = e.Error.Exception.Message;
 7             }
 8 
 9             if (e.Action == ValidationErrorEventAction.Removed)
10             {
11                 (e.OriginalSource as Control).Background = new SolidColorBrush(Colors.White);
12                 tbMessage.Text = "";
13             }
14         }

效果如下:

下载Demo