WPF ToolTip显示数据验证提示

WPF ToolTip显示数据验证提示

• 先创建一个验证条件类继承自ValidationRule,并实现INotifyPropertyChanged进行通知提醒界面

public class ValiRange : ValidationRule, INotifyPropertyChanged
    {
        public string errorMessage;
        public string ErrorMessage { get => errorMessage; set { errorMessage = value; OnPropertyChanged("ErrorMessage"); } }
        public event PropertyChangedEventHandler PropertyChanged;
        public void OnPropertyChanged(string propertyname)
        {
            if (this.PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(propertyname));
            }
        }

        public override ValidationResult Validate(object value, CultureInfo cultureInfo)
        {
            if (uint.TryParse(value.ToString(), out uint result))
            {
                if (result >= 0 && result <= 64)
                {
                    return ValidationResult.ValidResult;
                }
                else
                {
                    ErrorMessage = "请输入大于0小于64的整数！";
                    return new ValidationResult(false, "请输入大于0小于64的整数！");
                }
            }
            else
            {
                ErrorMessage = "请输入大于0小于64的整数！";
                return new ValidationResult(false, "请输入大于0小于64的整数！");
            }
        }
    }

• 界面使用BInding并设置ToolTip显示验证器提醒

 <TextBox x:Name="txt" Width="120" Height="40" ToolTip="{Binding ElementName=valis,Path=ErrorMessage,Mode=TwoWay}">
            <TextBox.Text>
                <Binding Path="Test.English" UpdateSourceTrigger="PropertyChanged">//需要将Text绑定到ViewModel属性
                    <Binding.ValidationRules>
                        <local:ValiRange x:Name="valis"/>
                    Binding.ValidationRules>
                Binding>
            TextBox.Text>
        TextBox>