I use Visual Studio 2012, and wrote some XAML(of WPF) code, just like this:
<StackPanel>
<Label Target="txt">UserName:</Label>
<TextBox Name="txt"></TextBox>
</StackPanel>
then, the compilation failed. It said to Label related-code,
Value cannot be null. Parameter name: context.
I don’t know its meaning. Did I miss anything?
It is a designer-only error. Code should compile without any issue.
EDIT: This exception is due to Silverlight not supporting this syntax :
Target="txt". this syntax is only supported by WPF. It’s a known bug in the designer, even if your project is a WPF project, and was caused by MS wanting to support design-time checks for Silverlight.If you don’t want the exception you have to use the full binding syntax (supported by WPF and Silverlight)