Validation Error : value "" could not be Converted xml in WPF ComboBox when Selected Item

Question

我已经尝试编写此验证代码，

 <ComboBox Name="CmbPlace" DisplayMemberPath="Name" 
                              SelectedValuePath="PlaceId" 
                              materialDesign:ComboBoxAssist.ShowSelectedItem="true"
                              Width="130" HorizontalContentAlignment="Right" Margin="5"
                              DropDownOpened="CmbPlace_OnDropDownOpened">
                        <ComboBox.Text>
                            <Binding Path="PlaceId">
                                <Binding.ValidationRules>
                                    <validation:RequireCmbValidation ValidatesOnTargetUpdated="True"/>
                                </Binding.ValidationRules>
                            </Binding>
                        </ComboBox.Text>

对于 TextBox 和另一个像这样的组件 Validation Working as well only for ComboBox 我遇到了这个问题这是我的验证，我知道这将 Return ValidationResult.ValidResult 成功

public class RequireCmbValidation: ValidationRule
{
    public override ValidationResult Validate(object value, CultureInfo cultureInfo)
    {
        if (!string.IsNullOrWhiteSpace(value?.ToString()))
            if (value.ToString() != "0")
                return ValidationResult.ValidResult;
            else
                return new ValidationResult(false, "Please Select one Item");
        return new ValidationResult(false, "Required!");
    }
}

Answer 1

我解决了我的问题

将<ComboBox.Text>替换为<ComboBox.SelectedValue>

5 小时后...但我希望这对其他人有帮助...

Validation Error : value "" could not be Converted xml in WPF ComboBox when Selected Item

Validation Error : value "" could not be Converted xml in WPF ComboBox when Selected Item

c#

wpf

mvvm