How to define/set variables in a static class in C#? Getting error 'The name [namespace.static_class.member] does not exist in the current context.'

Question

I'm trying to build a class that will optionally direct my trapped error conditions by writing a message to a TextBox (the reference to which is specified by the main program) and or throwing an exception.

The logic to write to the text box and/or throw an error is specified in the main program by setting the value of class member int ThrowWhen to a member of enum WhenToThrow . Here is the class:

public static class DoExceptions
{
    public static Windows.UI.Xaml.Controls.TextBox ExceptionTextBox;
    public static int ThrowWhen;
    public enum WhenToThrow { throw_null,  throw_never, throw_always, throw_if_no_output };

    private static int throwWhen;

    public static int ThrowWhen
    {
        get
        {
            return throwWhen;
        }

        set
        {
            throwWhen = value;
        }
    }

    public static void Action(string msg)  
    {
        if (ExceptionTextBox != null)
        {
            ExceptionTextBox.Text = msg;
            if ((int) ThrowWhen == (int)WhenToThrow.throw_always)
            {
                throw new Exception(msg);     
            }
        }
        else
        {
            if ((int)ThrowWhen == (int)WhenToThrow.throw_if_no_output)
            {
                throw new Exception(msg);
            }
        }
    }
}

The above class is defined in a namespace called MobileDAQ. (Everything else defined in that namespace is working.)

In my main program (which is a Windows Universal Blank App targeting Windows 8.1), I am trying to set the parameter ThrowWhen as follows:

MobileDAQ.DoExceptions.ThrowWhen = MobileDAQ.DoExceptions.throw_always; 

But both the left and right sides of the assignment throw the same error: "Error CS0103 The name 'MobileDAQ.DoExceptions.ThrowWhen' does not exist in the current context." , or ... MobileDAQ.DoExceptions.throw_always ... .

I must be making a stupid mistake (or else there's a serious caveat about static classes that thee doco doesn't give enough attention to), but everything I try either makes no difference or throws a new compile error.

Where am I going wrong?

Answer 1

throw_always is a member of WhenToThrow enum. It's not member of DoExceptions class. You missed the enum name:

MobileDAQ.DoExceptions.ThrowWhen = MobileDAQ.DoExceptions.WhenToThrow.throw_always; 
                                                               ^

Also I suggest you to use using directive to allow use types in MobileDAQ namespace:

using MobileDAQ;

...

DoExceptions.ThrowWhen = DoExceptions.WhenToThrow.throw_always; 

Or even with new C# 6 feature you can allow access static members:

using static MobileDAQ.DoExceptions;

...

ThrowWhen = WhenToThrow.throw_always; 

Answer 2

I got it! I was trying to do the assignment to ThrowWhen from within the class declarations section of the program. I moved it to the Grid_Loaded event routine and everything was fine.