如何在 XAML ResourceDictionary 中声明空字符串 [英] How to declare an empty string in XAML ResourceDictionary

问题描述

我有一个包含字符串的 ResourceDictionary:

I have a ResourceDictionary that contains strings:

<ResourceDictionary xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                    xmlns:sys="clr-namespace:System;assembly=mscorlib">
    <sys:String x:Key="Foo">Hello world</sys:String>
    ...
</ResourceDictionary>

这个字典是一个主题的一部分，在一些主题中，有些字符串是空的:

This dictionary is part of a theme, and in some themes, some of the strings are empty:

    <sys:String x:Key="Foo"></sys:String>

问题是在那种情况下，我得到一个 XamlParseException:

The trouble is that in that case, I get a XamlParseException:

无法创建类型为System.String"的对象.创建实例失败，这可能是由于没有公共默认构造函数'System.String'

Cannot create object of type 'System.String'. CreateInstance failed, which can be caused by not having a public default constructor for 'System.String'

我知道可以使用 <x:Static Member="sys:String.Empty"/> 在数组资源中声明一个空字符串，但我不想要一个数组...直接使用 x:Static 作为资源返回标记扩展名，而不是字符串.将 x:Static 放在 sys:String 元素中会产生与之前相同的错误.

I know it is possible to declare an empty string in an array resource, using <x:Static Member="sys:String.Empty" />, but I don't want an array... Using x:Static directly as the resource returns the markup extension, not the string. Putting x:Static in the sys:String element gives the same error as before.

是否可以将空字符串声明为 XAML 资源?怎么样?

Is it even possible to declare an empty string as an XAML resource? How?

推荐答案

使用 x:Static 声明它似乎对我来说很好用...

Declaring it using x:Static seems to work just fine for me...

<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                    xmlns:local="clr-namespace:Test"
            xmlns:sys="clr-namespace:System;assembly=mscorlib">
    <x:Static x:Key="empty" Member="sys:String.Empty" />
</ResourceDictionary>

 cc.Content = (string)FindResource("empty"); //Casts to string without exception

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