How do I reference a namespace to be used in immediate or quickwatch?

Question

Sometimes when I quickwatch an expression at runtime, the Quick Watch window shows an error saying the name does not exists in the current context. The same goes for the immediate window. The expression I try to evaluate, however, is perfectly recognized by the class, without throwing any compilation error.

For example, I can have the following line of code:

double x = Math.Pow(2,3);

If I stop the cursor on this line and quickwatch the "Math.Pow(2,3)" part, it gives me an error and I need to place a "System." before my expression; as I said, the same expression runs smoothly in the code window, so I'm not sure which is the "context" the error refers to.

Could it be that these debug windows reference namespaces declared in the class but can't do the same for namespace imported by the project?

Lookeron

Works for me in a Console Application. Are you using a special project template? – Platitude

You simply cant. Have to prefix the namespace. – Tepic

It also works fine without the namespace for me too. What edition/version/service pack of VS are you using? – Monia

I'm using VS2010 professional SP1 under 7 ultimate. – Lookeron

Answer 1

In my understanding the QuickWatch and the Immediate windows are executing the code / expressions under the current executing context, so once there is a using System; in place in the code, the quickwatch window will not give any issue. You may have encountered some visual studio bug. Try restarting VisualStudio and check again.

I have not encountered this kind of issue. This kind of issue will crop up when you try to Quick Watch Math.Pow(2d, 4d); when having the code like this System.Math.Pow(2d, 4d);

Trilogy

I encounter it all the time. So do my colleagues. Using VS2010 SP1 with regular C# class library projects. Sometimes it recognizes the namespace, sometimes it doesn't. Never found the pattern. I always thought it was a prevalent issue in VS and that everyone experiences it. – Brainstorm

Do you have any extensions related to debugging in VS2010, as i am also using the same VS2010 and have not run into this till now. hence it may be due to some extensions i guess. – Trilogy

Nope, no debugging extensions. – Brainstorm

Answer 2

Solution:

Go to your program.cs file and add the usings you want your immediate window to use, this works for both Console and Windows Forms applications

Refrence namespaces to Immediate Window in a Class Library Project

If you are using the Immediate Window in "Design Time" mode, and want reference some namespaces to it, you need to set the ouput mode to Windows Application, and create a program that does nothing.

1. Right click your project in solution explorer and click properties
2. Under Application, change the Output type: from Class-Library to Windows Application
3. Add the following dummy-class to your project:

Program.cs

using System;
//Add all the refrences you need immediate window to use here

namespace YourNamespace
{
    static class Program
    {
        static void Main()
        {

        }
    }
}

Zeb

⁺¹, adding a namespace to the «Program.cs» file indeed did the trick for Immediate window! – Wellwisher

Except in the case of System.Linq namespace and VS2015 lambda debugging, in source files where no linq expression has yet been executed. Add a line var temp = Enumerable.Range(1, 1); before your breakpoint and restart to solve this. – Coequal

This was an OK solution for me. – Ayana