displaying bitflags as enumerated text and not int

[Peted]

Hi

i am trying to make a small mdoification to and exisiting dll control,
in its source code.

Im trying to expose one of its internal properties so the user can set
it in the ide at designtime, but the property consists of enumerated
constants used in bit operations, and when the values are exposed they
show up as integers instead of the text contstants listed
EG

//Initial value
private int dwFlags = Gdi.PFD_DRAW_TO_WINDOW |
Gdi.PFD_SUPPORT_OPENGL | Gdi.PFD_DOUBLEBUFFER;

// I expose the property to the ide user here
#region DWFlags
/// <summary>
/// sets the OpenGL control's Flag properties.
/// </summary>
[Category("OpenGL Properties"), Description("Flag
properties.")]
public String DWFlags {
get {
return dwFlags);
}
set {
dwFlags = value);
}
}
#endregion DWFlags
When you see it in the ide the DWFlags value shows as 37, but i want
it to show as
PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER;

in the control field.

I also want the user to be able to enter the flags as the above text,
even adding more flags to also be used in this bit operation and have
it translated or sent to the control in form that it can be used.

the flags are used in the following opengl structure

Gdi.PIXELFORMATDESCRIPTOR pfd = new Gdi.PIXELFORMATDESCRIPTOR();// The
pixel format descriptor
pfd.nSize = (short) Marshal.SizeOf(pfd);
// Size of the pixel format descriptor
pfd.nVersion = 1;
// Version number (always 1)
--------------->>>i want to replace this line bellow

pfd.dwFlags =Gdi.PFD_DRAW_TO_WINDOW |
Gdi.PFD_SUPPORT_OPENGL | Gdi.PFD_DOUBLEBUFFER;

----------------------------->>> with pfd.dwFlags = dwFlags;

pfd.iPixelType = (byte) Gdi.PFD_TYPE_RGBA;
etc etc etc etc
You can see the flags are enumerated constants from opengl
Can anyone help please on how i can pass these flag data beckwards and
forwards to the control and have the user edit it, and still have it
come back and be usuable in the structure
thanks for any help

Peted

[Marc Gravell]

OK, you have an odd combination of int, string (so that your posted
code doesn't compile), and what perhaps could be an enum. Realistic
code would help people give a realistic answer!

However; *assuming* that Gdi doesn't declare a suitable enum, I would
simply do it myself; the following does most of what you want. If you
want a check-box style value-editor, then you'll need to add a custom
[Editor]; I'm pretty certain you could pick up a popup (or pop-down)
check-box style editor easily enough (it would take about 10 minutes
to write one from scratch).

If you don't want to go down the enum route, then you'd need to write
a TypeConverter, and specify this against the property; then you can
handle the parsing and formatting yourself - but I'd recommend using
enum!

Of course, if the "Gdi" class is declared in your project, then simply
define the enum values directly. Note that you can cast directly from
enum to/from int to get the int value to pass to whatever needs it.

using System;
using System.ComponentModel;
using System.Windows.Forms;
static class Program {
static void Main() {
Application.EnableVisualStyles();
using(Form form = new Form())
using (PropertyGrid grid = new PropertyGrid()) {
grid.Dock = DockStyle.Fill;
grid.SelectedObject = new SomeClass();
form.Controls.Add(grid);
Application.Run(form);
}
}
}
[Flags]
enum GdiDwFlags {
None = 0,
DrawToWindow = Gdi.PFD_DRAW_TO_WINDOW,
SupportOpenGl = Gdi.PFD_SUPPORT_OPENGL,
DoubleBuffer = Gdi.PFD_DOUBLEBUFFER
}
static class Gdi { // I'm making up the values... presumably defined
externally
public const int PFD_DRAW_TO_WINDOW = 1, PFD_SUPPORT_OPENGL = 2,
PFD_DOUBLEBUFFER = 4;
}
class SomeClass {
private GdiDwFlags dwFlags = GdiDwFlags.DrawToWindow |
GdiDwFlags.SupportOpenGl | GdiDwFlags.DoubleBuffer;
[Category("OpenGL Properties"), Description("Flag properties.")]
public GdiDwFlags DWFlags {
get {return dwFlags;}
set {dwFlags = value;}
}
}

[Peted]

Hi Marc

thankyou for your effort, i apollogies my description of what i was
after was realy bad.

I will repost my question with a better explanation

Peted

[Marc Gravell]

especially in the adding of events to the button click

b.Click += delegate { OnValueSelected(); };

This is an anonymous method; it is equivalent to having:
public void OKButtonClicked(object sender, EventArgs args) {
OnValueSelected(); // raise the ValueSelected event
}
and using
b.Click += new EventHandler(OKButtonClicked);

Basically, it just saves me some typing, which I consider a good thing.

[Peted]

thanks heaps

Peted
On Sun, 23 Sep 2007 02:07:14 -0700, Marc Gravell
<ma**********@gmail.comwrote:

>especially in the adding of events to the button click

b.Click += delegate { OnValueSelected(); };

This is an anonymous method; it is equivalent to having:
public void OKButtonClicked(object sender, EventArgs args) {
OnValueSelected(); // raise the ValueSelected event
}
and using
b.Click += new EventHandler(OKButtonClicked);

Basically, it just saves me some typing, which I consider a good thing.