Executing code before .NET's Main() method

Question

Is it possible to execute any user-provided code before the .NET Main method?

It would be acceptable if the code had to be unmanaged.

The reason for asking is that this might be a way to solve the problem of calling SetCurrentProcessExplicitAppUserModelID before any UI elements are displayed (as mentioned in Grouping separate processes in the Windows Taskbar)

Sure, if that solves the problem! I'm not afraid of C++ if that's what you're asking :-) — David Gardiner, Dec 19 '12 at 05:29

score 13 · Accepted Answer · answered Dec 19 '12 at 05:28

13

In C# you can add a static constructor to the class which contains the main method. The code in the static constructor will be executed before main.

answered Dec 19 '12 at 05:28

Andrew Cooper

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That certainly does execute before Main, though it doesn't seem resolve the issue of calling SetCurrentProcessExplicitAppUserModelID. Maybe the problem is it's a Console app – David Gardiner Dec 19 '12 at 05:40
Yes, changing to a Windows app instead of Console solved my other problem. – David Gardiner Dec 19 '12 at 23:24

score 2 · Answer 2 · answered Dec 19 '12 at 05:43

A static constructor will execute before Main, but only if the class is actually being referenced by something. Eg:

class ClassWStaticCon
{
    static ClassWStaticCon()
    {
        Console.WriteLine("Hello world!");
    }
}

...
static void Main(string[] args)
{
    Console.WriteLine("Hello main.");
}

Will print:

Hello main.

class ClassWStaticCon
{
    public static int SomeField;
    static ClassWStaticCon()
    {
        Console.WriteLine("Hello world!");
    }
}

...
static void Main(string[] args)
{
    ClassWStaticCon.SomeField = 0;
    Console.WriteLine("Hello main.");
}

Will print:

Hello world! Hello main.

If you want to control the order of execution then use a Queue of Action delegates http://msdn.microsoft.com/en-us/library/018hxwa8.aspx in a single static 'initialize all pre main stuff' class.

Executing code before .NET's Main() method

2 Answers2

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