上位机_WPF系列总结（WPF输入验证）

1、Xaml部分定义一个输入框作为测试；

<Grid>
        <StackPanel Margin="5" Orientation="Horizontal" Width="200" HorizontalAlignment="Center" VerticalAlignment="Center">   
            <TextBlock Text="姓名：" />
            <TextBox Name="NameTb" Width="100" ToolTip="{Binding RelativeSource={x:Static RelativeSource.Self}, Path=(Validation.Errors)[0].ErrorContent}">
                <TextBox.Text>
                    <Binding
                        NotifyOnValidationError="True"
                        Path="Name"
                        UpdateSourceTrigger="PropertyChanged">
                        <Binding.ValidationRules>
                            <local:CustomValidationRule ValidateType="Name" />
                        </Binding.ValidationRules>
                    </Binding>
                </TextBox.Text>
            </TextBox>
        </StackPanel>
    </Grid>

2、新定义一个静态资源，当检测到有Error的时候，输入框的边框部分进行红色展示；

<Window.Resources>
        <Style x:Key="basestyle" TargetType="TextBox">
            <Setter Property="Background" Value="AliceBlue" />
            <Style.Triggers>
                <Trigger Property="Validation.HasError" Value="True">
                    <Setter Property="BorderBrush" Value="Red" />
                </Trigger>
            </Style.Triggers>
        </Style>
 </Window.Resources>

3、定义CustomValidationRule类，写入校验规则；

public class CustomValidationRule : ValidationRule
    {
        public string ValidateType { get; set; }
        public override ValidationResult Validate(object value, CultureInfo cultureInfo)
        {
            try
            {
                string valueString = value?.ToString().Trim();
                if (ValidateType == "Name")
                {
                    string name = valueString;
                    if (!string.IsNullOrEmpty(name))
                    {
                        string errorMessage = string.Empty;

                        return name.Length > 5 ? new ValidationResult(false, "名称过长,名称长度不能超过5") : new ValidationResult(true, null);
                    }
                }
                return new ValidationResult(true, null);
            }
            catch (Exception e)
            {
                return new ValidationResult(false, e.Message);
            }
        }
    }

4、触发效果