OK     this.InitializeComponent(); 

Wrong  this.InitializeComponent;

另一种可能的解释是，您正在针对x86进行构建。右键单击解决方案并选择配置管理器。看看你是否在x86而不是任何CPU上构建。

我知道这是一个老问题了，但我们也遇到过类似的问题。我们能够使用VS2012构建一个项目，但不能从命令行使用msbuild。我进入。proj文件，并注意到它在默认的“PropertyGroup”部分下没有“ProjectTypeGuids”的记录，所以我添加了这个:

<ProjectTypeGuids>{60dc8134-eba5-43b8-bcc9-bb4bc16c2548};{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}</ProjectTypeGuids>

这是WPF的项目GUID。然后我删除并重新添加UserControl，它开始工作。我不确定我是否必须做最后一步，但现在它对我有用。

如果命名空间是正确的，那么也有一个相同的错误，

只需关闭应用程序并重新打开。

这也许能解决你的问题

.xaml文件的构建动作也必须设置为“Page”，当在项目之间移动xaml文件时，这个设置会丢失(至少在VS 2010中是这样)。

I had a problem similar to this in WPF. I had copied a usercontrol but had forgotten to rename the public ViewModel property in its.xaml.cs file for it. But still wasn't working. I eventually deleted all of the files inside the obj\debug type of folder for the project (we had this named differently). And rebuilt it. It still wasn't working, and I exited Visual Studio. (Before this I had at one point two instances of Visual Studio I think maybe.) The problem I had was that it was reporting it had this error when I had already fixed it! When I came back into Visual Studio (after deleting the debug stuff in obj), there finally was no error indicator. Then I rebuilt the project and now all was good!

这和我之前做的顺序不一样。它需要被简化。