New to C#-would like to add WndProc

Question

Everyone, I am just so new to C#, please help me...

I would like to add WndProc to process messages, I have look into properties but I don't see the thunderbolt to display function name so I can add one I like. I search the internet and see WndProc as

protected override void WndProc(ref Message msg) 
{
   //do something
}

I would like it to be generated for me, not to type it down ?

score 9 · Accepted Answer · answered Aug 29 '11 at 07:03

9

WndProc is not a .NET event handler; it's a window procedure, part of the native Win32 API. You won't get any code generation for it as an event handler in Visual Studio.

In Windows Forms all you have to do is override a form's existing WndProc() method and start coding. As it's found in the Form class, there is an autocomplete option for it if you type the following:

override WndProc

which then generates:

    protected override void WndProc(ref Message m)
    {
        base.WndProc(ref m);
    }

answered Aug 29 '11 at 07:03

BoltClock

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You mean I have to type that function prototype below the `public Form1(){....}` of the partial class Form1 ? – Pevus Aug 29 '11 at 07:06
@Pevus: That's right. But you don't have to type the whole thing, as there's autocomplete for overriding base methods. I've just expanded my answer to show that. – BoltClock Aug 29 '11 at 07:08
2

If you are new than chances are VERY high that you will not need this - you will certainly don't need it if you only want to dispatch some button-click, form-load, ... - messages! – Random Dev Aug 29 '11 at 07:20
Yeah I totally forgot to mention that. Window messages are very low level, you should stay away until you're more experienced with Windows programming. – BoltClock Aug 29 '11 at 07:31

score 5 · Answer 2 · edited Aug 29 '11 at 07:32

just to make this perfectly clear: it's rather improbable that you ever have to do something with WndProc inside winforms/wpf/whatever in the .net world. All this nasty stuff is abstracted and hidden away from you and I don't know a single case where I really needed/missed it.

In Winforms you just wire up events with

Eventname += EventHandlerMethod;

(or you can do such more advanced stuff with annonymous methods and lambdas but don't concern yourself to much with it at the moment).

The easiest way is to just use the Designer and hook your events there: enter image description here After subscribed to a event with this tool the editor will show you the handler it created and you can start coding away.

Here is a quick example: I just started a new project and added a single button "button1" onto the form: enter image description here

then I hook up the OnClick-Event of the button (select the button and goto the event-tab): enter image description here

and finaly I added code to change the buttons text to "clicked" into the codebehind:

using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace StackOverflowHelp1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
            // the following line is from InitializeComponent - here you can see how the eventhandler is hook
            // this.button1.Click += new System.EventHandler(this.OnButton1Clicked);
        }

        private void OnButton1Clicked(object sender, EventArgs e)
        {
            var button = sender as Button; // <- same as button1
            if (button == null) return; // <- should never happen, but who is to know?
            button.Text = "clicked";
        }
    }
}

that's all. The nasty dispatching of events is done by the framework.

What about textbox scrolling? http://stackoverflow.com/questions/14163007/catch-textbox-scroll-event — drzaus, Aug 12 '15 at 17:33
what about it? Is every event you have in Windows projected to some Winforms event? Well probably but see there is another accepted answer and you can probably use it (it's not like I constantly watch all my answers from 4 years ago any way ;) ) — Random Dev, Aug 12 '15 at 17:36
I was remarking on your opening statement on the improbability of needing `WndProc`; linking to that question was to indicate that there are people who need it. — drzaus, Aug 12 '15 at 18:14
ha, turns out there is an abstraction -- the ["hidden" `MouseWheel` event](http://stackoverflow.com/a/26672097/1037948). you win :) — drzaus, Aug 12 '15 at 18:20

New to C#-would like to add WndProc

2 Answers2