<newbie alert>
I'm attempting to expand on the WinApi winsamp.d gui example with some
controls, such as a single line edit control and a multiline edit control.

I can create the controls fine with CreateWindowA, but I'm having trouble using SendMessageA with a string for the lParam parameter.

hTextViewerEdit = CreateWindowA("EDIT", "", WS_CHILD | WS_VISIBLE |
WS_BORDER |
    ES_AUTOVSCROLL | WS_VSCROLL
  | ES_LEFT | ES_MULTILINE | ES_NOHIDESEL,
  115, 32, 260, 300, hWndMain, cast(HMENU) IDC_EDIT_TEXT_VIEWER, hInstance,
null);

  SendMessageA(hTextViewerEdit, WM_SETTEXT, 0, "Test");

The compiler complains that "Test" isn't compatible with int parameter it expects.

I've tried a variety of casts and temp variables to attempt to get SendMessageA to work, but haven't succeeded. I looked over the documentation, forum, and within phobos.d to try to figure out how to do this. How is this done?

TIA,
Lynn A.

"Test" is a D string, which is a four-byte length and a four-byte pointer. To pass to Win32 API you need the pointer, so cast as (char*), as in

>   SendMessageA(hTextViewerEdit, WM_SETTEXT, 0, (char*)"Test");




"Lynn Allan" <l.allan@att.net> wrote in message news:cd9seb$p5n$1@digitaldaemon.com...
> <newbie alert>
> I'm attempting to expand on the WinApi winsamp.d gui example with some
> controls, such as a single line edit control and a multiline edit control.
>
> I can create the controls fine with CreateWindowA, but I'm having trouble using SendMessageA with a string for the lParam parameter.
>
> hTextViewerEdit = CreateWindowA("EDIT", "", WS_CHILD | WS_VISIBLE |
> WS_BORDER |
>     ES_AUTOVSCROLL | WS_VSCROLL
>   | ES_LEFT | ES_MULTILINE | ES_NOHIDESEL,
>   115, 32, 260, 300, hWndMain, cast(HMENU) IDC_EDIT_TEXT_VIEWER, hInstance,
> null);
>
>   SendMessageA(hTextViewerEdit, WM_SETTEXT, 0, "Test");
>
> The compiler complains that "Test" isn't compatible with int parameter it expects.
>
> I've tried a variety of casts and temp variables to attempt to get SendMessageA to work, but haven't succeeded. I looked over the documentation, forum, and within phobos.d to try to figure out how to do this. How is this done?
>
> TIA,
> Lynn A.
>
>

Hi Matthew,

Thanks for the info ... and your patience with this newbie.

> "Test" is a D string, which is a four-byte length and a four-byte pointer.
To
> pass to Win32 API you need the pointer, so cast as (char*), as in
>
> >   SendMessageA(hTextViewerEdit, WM_SETTEXT, 0, (char*)"Test");

Almost. Without the deprecated flag, the 0.95 compiler was unhappy without:
cast(char*)"Test"

and was still unhappy trying to coerce from char* to LPARAM.

The following (hack?) works ok.
char* p = "Test1";
SendMessageA(hTextViewerEdit, WM_SETTEXT, 0, cast(int)p);

and this also works:
SendMessageA(hTextViewerEdit, WM_SETTEXT, 0, cast(int)cast(char*)"Test2");

Is this the proper / appropriate way to accomplish this?

Lynn A.

Lynn Allan wrote:
>>>  SendMessageA(hTextViewerEdit, WM_SETTEXT, 0, (char*)"Test");
> 
> 
> Almost. Without the deprecated flag, the 0.95 compiler was unhappy without:
> cast(char*)"Test"
> 
> and was still unhappy trying to coerce from char* to LPARAM.
> 
> The following (hack?) works ok.
> char* p = "Test1";
> SendMessageA(hTextViewerEdit, WM_SETTEXT, 0, cast(int)p);
> 
> and this also works:
> SendMessageA(hTextViewerEdit, WM_SETTEXT, 0, cast(int)cast(char*)"Test2");
> 
> Is this the proper / appropriate way to accomplish this?

Probably.

Just to speak up for D here, this is a problem with the Microsoft API, not with D.  D implicitly casts char[] to char*, so if Microsoft had decided to declare the parameter as char*, you never would have seen this problem.

Perhaps somebody should implement a wrapper function with a more sensible char* argument.

"Lynn Allan" <l.allan@att.net> wrote in message news:cdbc1i$1bfo$1@digitaldaemon.com...
> Hi Matthew,
>
> Thanks for the info ... and your patience with this newbie.
>
> > "Test" is a D string, which is a four-byte length and a four-byte pointer.
> To
> > pass to Win32 API you need the pointer, so cast as (char*), as in
> >
> > >   SendMessageA(hTextViewerEdit, WM_SETTEXT, 0, (char*)"Test");
>
> Almost. Without the deprecated flag, the 0.95 compiler was unhappy without:
> cast(char*)"Test"
>
> and was still unhappy trying to coerce from char* to LPARAM.
>
> The following (hack?) works ok.
> char* p = "Test1";
> SendMessageA(hTextViewerEdit, WM_SETTEXT, 0, cast(int)p);
>
> and this also works:
> SendMessageA(hTextViewerEdit, WM_SETTEXT, 0, cast(int)cast(char*)"Test2");
>
> Is this the proper / appropriate way to accomplish this?

Yes. Apologies for my arcane and sloppy advice. :)

"Russ Lewis" <spamhole-2001-07-16@deming-os.org> wrote in message news:cdbkhi$1e3d$1@digitaldaemon.com...
> Lynn Allan wrote:
> >>>  SendMessageA(hTextViewerEdit, WM_SETTEXT, 0, (char*)"Test");
> >
> >
> > Almost. Without the deprecated flag, the 0.95 compiler was unhappy without:
> > cast(char*)"Test"
> >
> > and was still unhappy trying to coerce from char* to LPARAM.
> >
> > The following (hack?) works ok.
> > char* p = "Test1";
> > SendMessageA(hTextViewerEdit, WM_SETTEXT, 0, cast(int)p);
> >
> > and this also works:
> > SendMessageA(hTextViewerEdit, WM_SETTEXT, 0, cast(int)cast(char*)"Test2");
> >
> > Is this the proper / appropriate way to accomplish this?
>
> Probably.
>
> Just to speak up for D here, this is a problem with the Microsoft API, not with D.  D implicitly casts char[] to char*, so if Microsoft had decided to declare the parameter as char*, you never would have seen this problem.
>
> Perhaps somebody should implement a wrapper function with a more sensible char* argument.

I often declare overloaded wrappers for this kind of stuff. Check out std/windows/registry.d

On Sat, 17 Jul 2004 09:36:02 -0700, Russ Lewis <spamhole-2001-07-16@deming-os.org> wrote:

> Lynn Allan wrote:
>>>>  SendMessageA(hTextViewerEdit, WM_SETTEXT, 0, (char*)"Test");
>>
>>
>> Almost. Without the deprecated flag, the 0.95 compiler was unhappy without:
>> cast(char*)"Test"
>>
>> and was still unhappy trying to coerce from char* to LPARAM.
>>
>> The following (hack?) works ok.
>> char* p = "Test1";
>> SendMessageA(hTextViewerEdit, WM_SETTEXT, 0, cast(int)p);
>>
>> and this also works:
>> SendMessageA(hTextViewerEdit, WM_SETTEXT, 0, cast(int)cast(char*)"Test2");
>>
>> Is this the proper / appropriate way to accomplish this?
>
> Probably.
>
> Just to speak up for D here, this is a problem with the Microsoft API, not with D.  D implicitly casts char[] to char*, so if Microsoft had decided to declare the parameter as char*, you never would have seen this problem.
>
> Perhaps somebody should implement a wrapper function with a more sensible char* argument.

(char *) is not the only type one might want to pass here, I have passed classes/structs/ints/floats...

Do you write a wrapper for each of those, or only 1 wrapper for (char *). If you write one wrapper wont you confuse someone who is looking for a way to pass something else, granted that is what this original function does.. writing lots of wrappers seems.. excessive when a cast will achieve what you need.

This appears to be another instance where a 'variant' type would be useful.

Regan

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