ValidationRule 中的 wpf 绑定属性

发布于 2024-12-04 20:21:17 字数 1142 浏览 4 评论 0原文

我有一个带有 2 个文本框的表单：

TotalLoginsTextBox
UploadsLoginsTextBox

我想限制 UploadsLoginsTextBox，因此文本的最大输入将是 TotalLoginsTextBox 的值。我还使用值转换器，因此我尝试限制最大值：

这是 XAML：

<!-- Total Logins -->
<Label Margin="5">Total:</Label>
<TextBox Name="TotalLoginsTextBox" MinWidth="30" Text="{Binding Path=MaxLogins, Mode=TwoWay}" />
<!-- Uploads -->
<Label Margin="5">Uploads:</Label>
<TextBox Name="UploadsLoginsTextBox" MinWidth="30">
    <TextBox.Text>
        <Binding Path="MaxUp" Mode="TwoWay" NotifyOnValidationError="True">
            <Binding.ValidationRules>
                <Validators:MinMaxRangeValidatorRule Minimum="0" Maximum="{Binding Path=MaxLogins}" />
            </Binding.ValidationRules>
        </Binding>
    </TextBox.Text>
</TextBox>

问题我收到以下错误：

无法在类型的“Maximum”属性上设置“Binding” 'MinMaxRangeValidatorRule'。 “绑定”只能设置在 DependencyObject 的 DependencyProperty。

进行绑定的正确方法是什么？

原文

i'm having a form with 2 text boxes:

TotalLoginsTextBox
UploadsLoginsTextBox

i want to limit UploadsLoginsTextBox so the maximum input for the text will be the value of the TotalLoginsTextBox.
i am also using a value converter so i try to bound the Maximum value:

this is the XAML:

<!-- Total Logins -->
<Label Margin="5">Total:</Label>
<TextBox Name="TotalLoginsTextBox" MinWidth="30" Text="{Binding Path=MaxLogins, Mode=TwoWay}" />
<!-- Uploads -->
<Label Margin="5">Uploads:</Label>
<TextBox Name="UploadsLoginsTextBox" MinWidth="30">
    <TextBox.Text>
        <Binding Path="MaxUp" Mode="TwoWay" NotifyOnValidationError="True">
            <Binding.ValidationRules>
                <Validators:MinMaxRangeValidatorRule Minimum="0" Maximum="{Binding Path=MaxLogins}" />
            </Binding.ValidationRules>
        </Binding>
    </TextBox.Text>
</TextBox>

the problem i am getting the following error:

A 'Binding' cannot be set on the 'Maximum' property of type
'MinMaxRangeValidatorRule'. A 'Binding' can only be set on a
DependencyProperty of a DependencyObject.

what is the proper way to do the binding ?

分享到QQ

分享到微博

如果你对这篇内容有疑问，欢迎到本站社区发帖提问参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。

发布评论

需要登录才能够评论，你可以免费注册一个本站的账号。

呆橘 2024-12-11 20:21:17

您看到此错误的原因是，如果要将 MinMaxRangeValidatorRule.Maximum 绑定到 MaxLogins，则它必须是 DependencyProperty，而它可能是一个简单的 CLR 属性。

真正的问题是 MinMaxRangeValidatorRule 应该能够从 ValidationRule 和 DependencyObject 继承（以使依赖属性可用）。这在 C# 中是不可能的。

我以这种方式解决了类似的问题：

为验证器规则命名

<验证器：MinMaxRangeValidatorRule Name="MinMaxValidator" 最小值="0" />

在代码后面，每当 MaxLogins 更改时设置最大值

public int MaxLogins 
{
    获取 { 返回 (int )GetValue(MaxLoginsProperty); }
    设置 { SetValue(MaxLoginsProperty, 值); }
}
公共静态 DependencyProperty MaxLoginsProperty = DependencyProperty.Register("MaxLogins ", 
                                                                                    类型（int）， 
                                                                                    类型（我的控件）， 
                                                                                    新的 PropertyMetadata(HandleMaxLoginsChanged));

私有静态无效 HandleMinValueChanged（DependencyObject d，DependencyPropertyChangedEventArgs e）
{
    mycontrol 源 = (mycontrol) d;
    source.MinMaxValidator.Maximum = (int) e.NewValue;
}

You're seeing this error because MinMaxRangeValidatorRule.Maximum needs to be a DependencyProperty if you want to bind it to MaxLogins, while it is probably a simple CLR property.

The real problem is that MinMaxRangeValidatorRule should be able to inherit from ValidationRule AND from DependencyObject (to make Dependency Properties available). This is not possible in C#.

I solved a similar problem in this way:

give a name to your validator rule

<Validators:MinMaxRangeValidatorRule Name="MinMaxValidator" Minimum="0" />

in code behind, set the Maximum value whenever MaxLogins changes

public int MaxLogins 
{
    get { return (int )GetValue(MaxLoginsProperty); }
    set { SetValue(MaxLoginsProperty, value); }
}
public static DependencyProperty MaxLoginsProperty = DependencyProperty.Register("MaxLogins ", 
                                                                                    typeof(int), 
                                                                                    typeof(mycontrol), 
                                                                                    new PropertyMetadata(HandleMaxLoginsChanged));

private static void HandleMinValueChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
    mycontrol source = (mycontrol) d;
    source.MinMaxValidator.Maximum = (int) e.NewValue;
}

回复收藏 0 原文

分分钟 2024-12-11 20:21:17

我猜“MinMaxRangeValidatorRule”是自定义的。

错误消息实际上非常明确，您需要将“Maximum”变量设置为依赖属性，如下所示：

public int Maximum
{
    get { return (int)GetValue(MaximumProperty); }
    set { SetValue(MaximumProperty, value); }
}

// Using a DependencyProperty as the backing store for Maximum.  This enables animation, styling, binding, etc...
public static readonly DependencyProperty MaximumProperty =
    DependencyProperty.Register("Maximum", typeof(int), typeof(MinMaxRangeValidatorRule), new UIPropertyMetadata(0));

您可以通过在 vs2010 中键入“propdp”来访问依赖属性片段。

I'm guessing the "MinMaxRangeValidatorRule" is something custom.

The error message is quite explicit actually, you need to make the "Maximum" variable a Dependency Property, like so:

public int Maximum
{
    get { return (int)GetValue(MaximumProperty); }
    set { SetValue(MaximumProperty, value); }
}

// Using a DependencyProperty as the backing store for Maximum.  This enables animation, styling, binding, etc...
public static readonly DependencyProperty MaximumProperty =
    DependencyProperty.Register("Maximum", typeof(int), typeof(MinMaxRangeValidatorRule), new UIPropertyMetadata(0));

You can access the dependency property snippet by typing "propdp" in vs2010.

回复收藏 0 原文

~没有更多了~