I am creating my own MainMenu control similar to VS.Net. (yes I know theirs
some out their).
I have predominatly been a web developer for about 5 years and am playing
with Windows forms. So this should help me learn.
My question is about IntPtr.
Basically what is it, I know its a pointer but what is a pointer.(of course
I know it points to something but how) .
In my MenuControl I needed a graphics object in my OnPaint override.
This works great but I dont know why...
//////////////////////////////////
protected override void OnPaint(PaintEv entArgs e) {
this.rmm_Graphi cs = Graphics.FromHw nd(this.Parent. Handle);
}
I think by understanding what pointers are and how they work I will
understand exactly how I extracted the grapics object from my containing
form.
Does any one know of some newbie windows resopurces that expain this on a
moronic level.
Thanks,
--
Ron Vecchi
3  1346 
Any intro to computer science text book using C. For example, mine was
"Introducti on to Computer Science Using C" by Roger Eggen. Highly
recommended.
The pointer contains a memory address. 32 bit operating systems use 32 bit
ints to address each available memory position. Conceptually, you can start
to get a handle on it by thinking of your street address "pointing" to your
house's physical location. Someone writes your address on a box and the USPS
delivers it to you. That's what a pointer can do.
Of coursed managed code complicates this because your "house" is moved when
the garbage collector runs.
"Ron Vecchi" <rv*****@xilehd vecchi.com> wrote in message
news:%2******** ********@TK2MSF TNGP09.phx.gbl. .. I am creating my own MainMenu control similar to VS.Net. (yes I know
theirs some out their).
I have predominatly been a web developer for about 5 years and am playing
with Windows forms. So this should help me learn.
My question is about IntPtr.
Basically what is it, I know its a pointer but what is a pointer.(of
course I know it points to something but how) .
In my MenuControl I needed a graphics object in my OnPaint override.
This works great but I dont know why...
//////////////////////////////////
protected override void OnPaint(PaintEv entArgs e) {
this.rmm_Graphi cs = Graphics.FromHw nd(this.Parent. Handle);
}
I think by understanding what pointers are and how they work I will
understand exactly how I extracted the grapics object from my containing
form.
Does any one know of some newbie windows resopurces that expain this on a
moronic level.
Thanks,
--
Ron Vecchi
ok, I think I understand. using the IntPtr is like saying "at this memory
location"
so in my case am I abstractly saying "give me the graphics object from the
form at this memory location"
Oh, also Im an idiot, I didn't realize that the PaintEventArgs supplied a
graphics object. Although that didn't stop me from still wondering about
the IntPtr. It just accelerated it.
"Mountai Bikn' Guy" <vc@attbi.com > wrote in message
news:gyZEb.5989 81$HS4.4389660@ attbi_s01... Any intro to computer science text book using C. For example, mine was
"Introducti on to Computer Science Using C" by Roger Eggen. Highly
recommended.
The pointer contains a memory address. 32 bit operating systems use 32 bit
ints to address each available memory position. Conceptually, you can
start to get a handle on it by thinking of your street address "pointing" to
your house's physical location. Someone writes your address on a box and the
USPS delivers it to you. That's what a pointer can do.
Of coursed managed code complicates this because your "house" is moved
when the garbage collector runs.
"Ron Vecchi" <rv*****@xilehd vecchi.com> wrote in message
news:%2******** ********@TK2MSF TNGP09.phx.gbl. .. I am creating my own MainMenu control similar to VS.Net. (yes I know
theirs some out their).
I have predominatly been a web developer for about 5 years and am
playing with Windows forms. So this should help me learn.
My question is about IntPtr.
Basically what is it, I know its a pointer but what is a pointer.(of
course I know it points to something but how) .
In my MenuControl I needed a graphics object in my OnPaint override.
This works great but I dont know why...
//////////////////////////////////
protected override void OnPaint(PaintEv entArgs e) {
this.rmm_Graphi cs = Graphics.FromHw nd(this.Parent. Handle);
}
I think by understanding what pointers are and how they work I will
understand exactly how I extracted the grapics object from my containing
form.
Does any one know of some newbie windows resopurces that expain this on
a moronic level.
Thanks,
--
Ron Vecchi
Personally, I would first try to understand pointers outside the context of
dotnet. I wouldn't try to understand IntPtr without understanding a plain
generic pointer. That's just my opinion. BTW, the text book I mentioned is
available for $15 used at http://www.amazon.com/exec/obidos/tg...books&n=507846
But I'm sure you can find coverage of this topic by searching on Google.
In general, a pointer holds the address of another variable. It's that
simple.
"Ron Vecchi" <rv*****@xilehd vecchi.com> wrote in message
news:eS******** ******@TK2MSFTN GP10.phx.gbl... ok, I think I understand. using the IntPtr is like saying "at this
memory location"
so in my case am I abstractly saying "give me the graphics object from the
form at this memory location"
Oh, also Im an idiot, I didn't realize that the PaintEventArgs supplied a
graphics object. Although that didn't stop me from still wondering about
the IntPtr. It just accelerated it.
"Mountai Bikn' Guy" <vc@attbi.com > wrote in message
news:gyZEb.5989 81$HS4.4389660@ attbi_s01... Any intro to computer science text book using C. For example, mine was
"Introducti on to Computer Science Using C" by Roger Eggen. Highly
recommended.
The pointer contains a memory address. 32 bit operating systems use 32
bit ints to address each available memory position. Conceptually, you can start to get a handle on it by thinking of your street address "pointing" to
your house's physical location. Someone writes your address on a box and the
USPS delivers it to you. That's what a pointer can do.
Of coursed managed code complicates this because your "house" is moved
when the garbage collector runs.
"Ron Vecchi" <rv*****@xilehd vecchi.com> wrote in message
news:%2******** ********@TK2MSF TNGP09.phx.gbl. .. I am creating my own MainMenu control similar to VS.Net. (yes I know
theirs some out their).
I have predominatly been a web developer for about 5 years and am
playing with Windows forms. So this should help me learn.
My question is about IntPtr.
Basically what is it, I know its a pointer but what is a pointer.(of
course I know it points to something but how) .
In my MenuControl I needed a graphics object in my OnPaint override.
This works great but I dont know why...
//////////////////////////////////
protected override void OnPaint(PaintEv entArgs e) {
this.rmm_Graphi cs = Graphics.FromHw nd(this.Parent. Handle);
}
I think by understanding what pointers are and how they work I will
understand exactly how I extracted the grapics object from my
containing form.
Does any one know of some newbie windows resopurces that expain this
on a moronic level.
Thanks,
--
Ron Vecchi
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