由网友(你被父母安稳的爱着)分享简介：当我尝试设置通过 WindowStartupLocation 属性二传手在的ResourceDictionary ，我收到了 XamlParseException ：When I attempt to set the WindowStartupLocation property through a Setter wi...

当我尝试设置通过 WindowStartupLocation 属性二传手在的ResourceDictionary ，我收到了 XamlParseException ：

When I attempt to set the WindowStartupLocation property through a Setter within a ResourceDictionary, I get a XamlParseException:

设置属性System.Windows.Setter.Property'引发了异常。行号'x'和线的位置Y。

'Set property 'System.Windows.Setter.Property' threw an exception.' Line number 'x' and line position 'y'.

的内部异常是 ArgumentNullException ：

值不能为空。参数名：属性

Value cannot be null. Parameter name: property.

我的资源字典中的风格是：

My style within the resource dictionary is:

<Style TargetType="Window" x:Key="WindowStyle">
    <Setter Property="SizeToContent" Value="WidthAndHeight" />
    <Setter Property="ResizeMode" Value="CanMinimize" />
    <Setter Property="WindowStartupLocation" Value="CenterOwner" />
</Style>

这个问题是不是与使用的ResourceDictionary ，因为当我删除 WindowStartupLocation ，其他两个性能（ SizeToContent 和 ResizeMode ）设置为预期引用该风格的窗户：

The issue is not with the use of the ResourceDictionary, since when I remove the WindowStartupLocation, the other two properties (SizeToContent and ResizeMode) are set as expected on windows which reference the style:

<Window x:Class="WpfApplication1.MyWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Style="{DynamicResource WindowStyle}">
    <Window.Resources>
        <ResourceDictionary Source="MyResourceDictionary.xaml" />
    </Window.Resources>
</Window>

有没有人遇到过吗？它是WPF的一个bug /限制吗？

Has anyone encountered this? Is it a bug/limitation of WPF?

P.S。我知道，这个问题类似于Window从资源字典的启动位置，但没有足够的信息是在随后没有解决其他问题提供的。

P.S. I know that this question is similar to Window Startup Location from resource dictionary, but not enough information was provided in the other question which subsequently remained unsolved.

推荐答案

问题是，WindowStartupLocation不是一个DependencyProperty的，所以你不能将其设置在风格的引领者。展望ILSpy二传手电话

The problem is that WindowStartupLocation is not a DependencyProperty so you can't set it in the style setter. Looking in ILSpy the Setter calls

CheckValidProperty(DependencyProperty property)

和抛出一个NullArgumentException。

and throws a NullArgumentException.

正如WindowStartupLocation只是一个CLR属性，它不能以这种方式设置

As WindowStartupLocation is just a CLR property, it can't be set in this way.

编辑： 为了应对意见。你仍然可以使用的ResourceDictionary ：

<Application.Resources>
    <ResourceDictionary>
        <Style x:Key="WindowStyle" TargetType="Window">
            <Setter Property="SizeToContent" Value="WidthAndHeight" />
            <Setter Property="ResizeMode" Value="CanMinimize" />
        </Style>
        <WindowStartupLocation x:Key="WSL">CenterOwner</WindowStartupLocation>
    </ResourceDictionary>
</Application.Resources>

<Window x:Class="WpfApplication7.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"            
        WindowStartupLocation="{StaticResource WSL}"
        Style="{StaticResource WindowStyle}" />