"The name does not exist in the namespace error" in XAML

Question

I know this is a recurring error but I can't seem to get around it. Intellisense does recognize the name of my custom control and suggests to add the proper using: directives, but not only XAML designer doesn't find the name of the control but I can't get through compilation either.

The custom control is a public class defined as

namespace MyApp.CustomControls
{
    public class CustomTextBox : TexBox
    {
        ...
    }
}

And in my MainPage.xaml

<Page ...
xmlns:customControls="using:MyApp.CustomControls">
      ...
      <customControls:CustomTextBox/>
      ...
</Page>

This does not render in design nor compile. This answer and the ones below are not working for me.

The error message:

Error XDG0008 The name "CustomTextBox" does not exist in the namespace "using:MyApp.CustomControls".

From the very link you linked, try using `clr-namespace` instead of `using` — Rafalon, May 31 '18 at 08:32
Not working either. As far as I know, `using` is the syntax to use in UWP. — rzippo, May 31 '18 at 08:38
It was rather to prove that I've done my research and nothing there is working, and avoid a `duplicate` flag pointing to an outdated question — rzippo, May 31 '18 at 08:43
Does this answer your question? [The name does not exist in the namespace error in XAML](https://stackoverflow.com/questions/14665713/the-name-does-not-exist-in-the-namespace-error-in-xaml) — StayOnTarget, Apr 07 '20 at 19:01

score 2 · Accepted Answer · answered Jun 01 '18 at 02:16

2

Your code should works well after you build the project, and it works well in my side using your above code. Try to clean your solution or delete the bin and obj folders in your project then rebuild your app again. Also try to restart your Visual Studio. If it still happens, you can provide a reproducible sample to help me look into this issue.

answered Jun 01 '18 at 02:16

Breeze Liu - MSFT

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Exactly! In my case the solution was deleting my repository (means all project files) and cloning it again. This way you make sure that even those git-ignored files are deleted. – Emir Mar 19 '21 at 16:57

score 0 · Answer 2 · answered Jan 10 '21 at 18:46

I've seen quite a lot solutions saying that you should rebuild the project, restart Visual Studio or restart the machine. What worked for me was specifying the assembly in the namespace reference, that is: xmlns:the_namespace="clr-namespace:the_namespace" - produces the above error. xmlns:the_namespace="clr-namespace:the_namespace;assembly=the_assembly" - works well.

score 0 · Answer 3 · answered Nov 20 '21 at 21:07

I got a version of this error in my embedded UserControl when I tried to use the Name property in my XAML instead of using x:Name. In other words, when my XAML code looked like this:

myUserControls="using:MyUserControls"

<myUserControls:GraphCanvas Name="GraphCanvas" />

I got an error that 'The name "GraphCanvas" does not exist in the namespace "using:MyUserControls"'. When I changed one line of code to this:

<myUserControls:GraphCanvas x:Name="GraphCanvas" />

Everything built just fine.

I'm dropping this solution here because it took me about a day and a half to figure out this problem and this was the only stackoverflow page I found when I searched the error string. Hopefully I will save someone else the hassle I went through.

"The name does not exist in the namespace error" in XAML

3 Answers3