WPF 自动验证

WPF中TextBox的自动验证：

演示 ：

用以下两个TextBox分别显示验证IP和非空值验证，先看效果：

IP自动验证效果：

非空值自动验证效果：

第一步：定义TextBox验证的样式：

<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">

    <Style x:Key="ValidationTextBoxStyle" TargetType="{x:Type TextBox}">
        <Setter Property="Validation.ErrorTemplate">
            <Setter.Value>
                <ControlTemplate>
                    <DockPanel LastChildFill="True">
                        <TextBlock DockPanel.Dock="Right"
                                           Foreground="Red" FontSize="14" FontWeight="Bold"
                                           ToolTip="{Binding ElementName=adornerPlaceholder,
                                           Path=AdornedElement.(Validation.Errors)[0].ErrorContent}">
                                    *
                        </TextBlock>
                        <Border BorderBrush="Red" BorderThickness="1" CornerRadius="3">
                            <AdornedElementPlaceholder Name="adornerPlaceholder"></AdornedElementPlaceholder>
                        </Border>
                    </DockPanel>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
        <Style.Triggers>
            <Trigger Property="Validation.HasError" Value="true">
                <Setter Property="ToolTip"
                                Value="{Binding RelativeSource={RelativeSource Self},
                                Path=(Validation.Errors)[0].ErrorContent}"/>
            </Trigger>
        </Style.Triggers>
    </Style>
</ResourceDictionary>

第二步：绑定上面的样式：

<TextBox x:Name="TxDataBaseIP" Style="{DynamicResource ValidationTextBoxStyle}" .....

<TextBox x:Name="TbDataBaseAcount" Style="{DynamicResource ValidationTextBoxStyle}" ......

第三步：为Text的Text属性定义和添加验证规则：

定义验证规则：

using System.Text.RegularExpressions;
using System.Windows.Controls;

namespace NCS.Client.WPF.Resources.Validations
{
    public class NotNullValidationRule : ValidationRule
    {
        public override ValidationResult Validate(object value, System.Globalization.CultureInfo cultureInfo)
        {
            if (string.IsNullOrEmpty(value as string) || string.IsNullOrWhiteSpace(value as string))
            {
                return new ValidationResult(false, "不能为空！");
            }
            return new ValidationResult(true, null);
        }
    }
    public class IPAddressRule : ValidationRule
    {
        public override ValidationResult Validate(object value, System.Globalization.CultureInfo cultureInfo)
        {
            string IPAddress = value as string;

            if (!string.IsNullOrWhiteSpace(IPAddress))
            {
                string IPAddressFormartRegex = @"^(d{1,2}|1dd|2[0-4]d|25[0-5]).(d{1,2}|1dd|2[0-4]d|25[0-5]).(d{1,2}|1dd|2[0-4]d|25[0-5]).(d{1,2}|1dd|2[0-4]d|25[0-5])$";

                // 检查输入的字符串是否符合IP地址格式
                if (!Regex.IsMatch(IPAddress, IPAddressFormartRegex))
                {
                    return new ValidationResult(false, "IP地址格式不正确");
                }
            }
            return new ValidationResult(true, null);
        }
    }
}

绑定规则：

                            <TextBox.Text>
                                 <Binding Path="DataBaseIp" Mode="TwoWay" 
                                     UpdateSourceTrigger="PropertyChanged">
                                    <Binding.ValidationRules>
                                        <validations:IPAddressRule/>
                                    </Binding.ValidationRules>
                                 </Binding>
                            </TextBox.Text>

                        <TextBox.Text>
                            <Binding Path="DataBaseAccount" 
                                     Mode="TwoWay" UpdateSourceTrigger="PropertyChanged">
                                <Binding.ValidationRules>
                                    <validations:NotNullValidationRule/>
                                </Binding.ValidationRules>
                            </Binding>
                        </TextBox.Text>

完整的控件xaml代码：

                <StackPanel Orientation="Horizontal" Height="30" VerticalAlignment="Top">
                    <TextBlock Text="数  据  库 IP" Width="70" VerticalAlignment="Center"/>
                    <TextBox x:Name="TxDataBaseIP" Style="{DynamicResource ValidationTextBoxStyle}"
                             MaxWidth="150" Width="150" Height="25"
                             HorizontalAlignment="Center" VerticalAlignment="Center">
                            <TextBox.Text>
                                 <Binding Path="DataBaseIp" Mode="TwoWay" 
                                     UpdateSourceTrigger="PropertyChanged">
                                    <Binding.ValidationRules>
                                        <validations:IPAddressRule/>
                                    </Binding.ValidationRules>
                                 </Binding>
                            </TextBox.Text>
                    </TextBox>
                </StackPanel>
                <StackPanel Orientation="Horizontal" Height="35" VerticalAlignment="Top">
                    <TextBlock Text="数据库账户" Width="70" VerticalAlignment="Center"/>
                    <TextBox x:Name="TbDataBaseAcount" Style="{DynamicResource ValidationTextBoxStyle}"
                             MaxWidth="150" Width="150" Height="25"
                             HorizontalAlignment="Center" VerticalAlignment="Center">
                        <TextBox.Text>
                            <Binding Path="DataBaseAccount" 
                                     Mode="TwoWay" UpdateSourceTrigger="PropertyChanged">
                                <Binding.ValidationRules>
                                    <validations:NotNullValidationRule/>
                                </Binding.ValidationRules>
                            </Binding>
                        </TextBox.Text>
                    </TextBox>
                </StackPanel>

【the end】

后记：

      1.有个缺陷的：一开始初始化界面的时候没有进行验证，必须是输入一次，以后才进行验证。如下图所示：

         

　　2. 上面的文章描述是基于我的一个实际项目编写的，有网友可能需要源码,现在我从原来的项目中剥离出这部分知识的代码部分，所以下载到的源码与上述的代码的

    命名空间不一致。

源码下载：

链接：http://pan.baidu.com/s/1jGE9V0q 密码：05g3

 拓展学习：

　　Regex Validation in WPF

　　http://www.codeproject.com/Articles/15610/Regex-Validation-in-WPF