WPF使用ValidationRules对MVVM架构数据验证

                        <TextBox  Margin="15 0 10 0" 
                                 Style="{StaticResource MaterialDesignFloatingHintTextBox}"  materialDesign:HintAssist.Hint="登录名 *">
                            <TextBox.Text>
                                <Binding Path="Model.Account" UpdateSourceTrigger="PropertyChanged" NotifyOnValidationError="True">
                                    <Binding.ValidationRules>
                                        <domain:CustomizeValidationRule validationType="Str" 
                                                                        minLength="3" maxLength="10"
                                                                        errORMessage="输入长度范围 [3-10]字" 
                                                                        ValidatesOnTargetUpdated="True" />
                                    </Binding.ValidationRules>
                                </Binding>
                            </TextBox.Text>
                        </TextBox>

public interface IValidationExceptionHandler
    {
        /// <summary>
        /// 是否有效
        /// </summary>
        bool IsValid
        {
            get;
            set;
        }
    }

    /// <summary>
    /// 验证行为类,可以获得附加到的对象
    /// </summary>
    public class ValidationExceptionBehavior : Behavior<FrameworkElement>
    {
        /// <summary>
        /// 错误计数器
        /// </summary>
        private int _validationExceptionCount = 0;
        
        /// <summary>
        /// 附加对象时
        /// </summary>
        protected override void OnAttached()
        {
            //附加对象时，给对象增加一个监听验证错误事件的能力，注意该事件是冒泡的
            this.AssociatedObject.AddHandler(Validation.ErrorEvent, new EventHandler<ValidationErrorEventArgs>(this.OnValidationError));
        }
        
        #region 获取实现接口的对象

        /// <summary>
        /// 获取对象
        /// </summary>
        /// <returns></returns>
        private IValidationExceptionHandler GetValidationExceptionHandler()
        {
            if (this.AssociatedObject.DataContext is IValidationExceptionHandler)
            {
                var handler = this.AssociatedObject.DataContext as IValidationExceptionHandler;

                return handler;
            }

            return null;
        }

        #endregion
        
        #region 验证事件方法

        /// <summary>
        /// 验证事件
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void OnValidationError(object sender, ValidationErrorEventArgs e)
        {
            try
            {
                var handler = GetValidationExceptionHandler();

                var element = e.OriginalSource as UIElement;

                if (handler == null || element == null)
                    return;

                if (e.Action == ValidationErrorEventAction.Added)
                {
                    _validationExceptionCount++;
                    
                }
                else if (e.Action == ValidationErrorEventAction.Removed)
                {
                    _validationExceptionCount--;
                }
                handler.IsValid = _validationExceptionCount == 0;
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }

        #endregion
    }

   <i:Interaction.Behaviors>
        <domain:ValidationExceptionBehavior></domain:ValidationExceptionBehavior>
    </i:Interaction.Behaviors>

        public override void Save()
        {
            if (!this.IsValid)
            {
                MessageBox.Show("输入的格式有误,请重新输入!");
                return;
            }
            base.Save();
        }