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Accsesing a string in an array of struct
I have the following code : 


sm STRUCT

     iIndex 	DW ? ;

     szLabel 	DB 50 DUP  (0);

     szDesc 	DB 50 DUP  (0);

sm ENDS

.data

sysmetrics \

sm  <SM_CXSCREEN,	"SM_CXSCREEN","Screen width in pixels">

sm  <SM_CYSCREEN,	"SM_CYSCREEN","Screen height in pixels">

sm  <SM_CXVSCROLL,"SM_CXVSCROLL","Vertical scroll width">

sm  <SM_CYHSCROLL,"SM_CYHSCROLL","Horizontal scroll height">

sm  <SM_CYCAPTION,"SM_CYCAPTION","Caption bar height">

sm  <SM_CXBORDER,"SM_CXBORDER","Window border width">

sm  <SM_CYBORDER,	"SM_CYBORDER","Window border height">



NUMPOINT equ ($-sysmetrics)/sizeof sm





.ELSEIF eax==WM_PAINT

	invoke BeginPaint,hWnd, addr ps

	mov hdc,eax

	push esi

	mov esi,offset sysmetrics

	assume esi: PTR sm

	xor ecx,ecx

	.repeat

		push ecx

		mov eax, cyChar

		mul ecx

		mov edx,eax

		lea ebx,[esi].szLabel

		mov al,[ebx]

		xor ah,ah

		.WHILE al

			inc ah

			inc ebx

			mov al,[ebx]

		.ENDW

		xor ebx,ebx

		mov bl,ah

		invoke TextOut,hdc,0,edx,addr [esi].szLabel,ebx

		add esi, sizeof sm

		pop ecx

		inc ecx

	.until esi == NUMPOINT * sizeof sm

	assume esi:nothing

	pop esi			

	invoke EndPaint,hWnd,addr ps

	ret

when I run the Program it shows only the first line and gives a windows error message.

1. where is the problem; I tried to solve this problem more the 3h :(

2. is there a better way to find the size of a sting ?

peace
Posted on 2004-10-01 05:45:52 by mistronr1
Accsesing a string in an array of struct
Use the StrLen supplied in the M32.LIB included with masm32.
You could also hardcode the string length in the structure, if it doesn't change.

I also see a space in your strings for Vertical scroll width, horizontal scroll width, etc. Might be a bad cut and paste tho.
Posted on 2004-10-07 09:34:52 by drarem
Accsesing a string in an array of struct
hi mistronr1

i just had a look at ur code and could not figure out why??? 


.WHILE al 

         inc ah 

         inc ebx 

         mov al,[ebx] <---------------this one

.ENDW

my question is can we put value of ebx (a register) in al (lower order bits of accumulator).
according to me its buggy there.if am wrong pay no heed to my post.
thank you
nickdigital
Posted on 2004-10-07 14:16:40 by nickdigital
Accsesing a string in an array of struct
...
my question is can we put value of ebx (a register) in al (lower order bits of accumulator).
according to me its buggy there.if am wrong pay no heed to my post.
thank you
nickdigital


The square brackets around ebx mean to load whatever is in memory at offset ebx into al. So in this case he loads the byte at offset ebx into al to check for the NULL terminator...the fact that ebx and al aren't the same size doesn't matter in this case.
Posted on 2004-10-07 15:15:55 by sirchess
Accsesing a string in an array of struct
hi sirchess,
thanks a lot for clearing my doubt.
nickdigital
Posted on 2004-10-07 15:29:20 by nickdigital
Accsesing a string in an array of struct
Hi guys
I did some changes to the code and still having some problems.

Drarem : I know I could use StrLen, but I want to be able to do it my selv to, I realy need to understand how addressing works in a strucutre, and by the way the space at the end of each line shouldn't matter, it has to be treated as part of the string (I guess).
OK the application writes the first line and the something goes wrong, I am trying to translate some code from from windows programing by Charles Petzold.

thanks for all the replys

peace
Posted on 2004-10-11 21:40:35 by mistronr1
Accsesing a string in an array of struct
I think the problem is that you have to save and restore the EBX register before you invoke any windows function.
Posted on 2004-10-14 05:20:59 by GorillaCoder