Win32汇编学习[7]: 定义符号常量(=、EQU、TEXTEQU)

关于符号常量 =的例子

main proc
PrintDec n ;2
ret
main endp
end main
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Equ的一个例子

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; Test13_2.asm
.386
.model flat,stdcall

include   windows.inc
include   kernel32.inc
include   masm32.inc
include   debug.inc
includelib kernel32.lib
includelib masm32.lib
includelib debug.lib

.data
    num1 equ 2        ; equ 可以定义整数和整数表达式
    num2 equ 3        ; 它不能像 = 一样重复定义
    num3 equ num1+num2 ; (我尝试了重复定义, 竟然有时也可以, 只是偶尔)

    txt equ <'Asm'> ; 可用 equ 定义字符串, 应使用 <>

    szTxt db txt, 0   ; 使用 equ 定义的常量
.code
main proc
    PrintDec num3    ;5
    PrintString szTxt ;Asm
   ret
main endp
end main

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Equ函数宏定义

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.386
.model flat,stdcall

include   windows.inc
include   kernel32.inc
includelib kernel32.lib
include   user32.inc
includelib user32.lib

; 用 equ 给函数重命名Msg equMessageBox
Exit equ <ExitProcess> ;尖括号可保证字符串的完整、并避免和关键字冲突
; 甚至代替整个表达式
ShowMsg equ <invoke MessageBox, NULL,addr szMsg,addr szCaption, MB_OK>

.data
    szMsg      db   'Hello World!', 0
    szCaption db   'Hi', 0
.code
main proc
   invoke Msg, NULL,addr szMsg,addr szCaption, MB_OK
   ShowMsg
   invoke Exit, NULL
main endp
end main

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textequ

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; Test13_4.asm
.386
.modelflat,stdcall

include   windows.inc
include   kernel32.inc
includelib kernel32.lib
include   user32.inc
includelib user32.lib

Msg textequ MessageBox
Exit textequ <ExitProcess>
ShowMsg textequ <invoke MessageBox, NULL,addr szMsg,addr szCaption, MB_OK>

.data
    szMsg    db 'Hello World!', 0
    szCaption db 'Hi', 0
.code
main proc
   invoke Msg, NULL,addr szMsg,addr szCaption, MB_OK
    ShowMsg
   invoke Exit, NULL
main endp
end main

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.386
.model flat,stdcall

include   windows.inc
include   kernel32.inc
include   masm32.inc
include   debug.inc
includelib kernel32.lib
includelib masm32.lib
includelib debug.lib

.data
    num1 equ 2              ; 这里的 equ 换做 textequ 不行
    num2 textequ <3>        ; 如果用 textequ 定义整数或表达式也要放在 <> 中
    num3 textequ <num1+num2> ; 这曾是 num3 equ num1+num2

    txt textequ <'Asm'>    ;
    txt textequ <'Delphi'> ; textequ 可重复定义

    szTxt db txt, 0
.code
main proc
    PrintDec num3    ;5
    PrintString szTxt ;Delphi
   ret
main endp
end main
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