What happens if class is not available?

[Diego Armando Maradona]

I have "MyProject.Commons.frmMessageBox"

if I wanna create it, doing this,

using (MyProject.Commons.frmMessageBox xFrm = new
MyProject.Commons.frmMessageBox())
{
xFrm.ShowDialog();
}

if I do not know "MyProject.Commons.frmMessageBox" is available or not and
want to handle this situation like this

if (Available("MyProject.Commons.frmMessageBox"))
{
ShowCustomDialog("MyProject.Commons.frmMessageBox");
}

This is possible ?

 

[Ciaran O''Donnell]

Why would it not be available? If it not referenced by your project, you will
get a compiler error and visual studio, you will get a compiler warning.

 

[Simon Tamman]

Yes, you could probably do something funky with reflection and exception
handling to do this. However I agree with the above poster, if you're trying
to do this you've probably made an incorrect design decision somewhere else.

 

[Michael Justin]

Why would it not be available? If it not referenced by your project, you will
get a compiler error and visual studio, you will get a compiler warning.

An assembly containing the referenced class could be replaced later (at
runtime) - just guessing: maybe .NET will display an 'Open File' Dialog
in this case and friendly ask the user to locate a file which contains
the class "MyProject.Commons.frmMessageBox" ...

Error messages are so medieval ;-)

Best Regards

 

[Ciaran O''Donnell]

The runtime will through an error if the assembly containing the type has
been replaced with a version that doesnt contain it. There is sadly no nice
OpenFileDialog.

 

[John B]

I have "MyProject.Commons.frmMessageBox"

if I wanna create it, doing this,

using (MyProject.Commons.frmMessageBox xFrm = new
MyProject.Commons.frmMessageBox())
{
xFrm.ShowDialog();
}

if I do not know "MyProject.Commons.frmMessageBox" is available or not
and want to handle this situation like this

if (Available("MyProject.Commons.frmMessageBox"))
{
ShowCustomDialog("MyProject.Commons.frmMessageBox");
}

This is possible ?

I think what you want in this case is a plugin architecture with a
default fallback that just shows a normal messagebox.
You would have to load the assembly dynamically if it exists.
Google c# plugin and you should see how you could do it.

JB