String 程序集x86日期到编号-将字符串拆分为较小的部分

事实上，我希望在一个问题上被指向正确的方向

我希望将x86汇编中的日期从格式“DD-MMM-YYYY”转换为唯一的数字，以便稍后对其进行气泡排序并最终转换回

因此，当我有一个字符串输入时，即： .数据 inDate dw“1993年9月8日”

我想把它分成两部分

day = "08"
month = "SEP"
year = "1993"

这样我可以进一步处理它（我将把SEP转换为“7”，等等）

所以我的问题是，什么是一种简单有效的方式来分解日期（代码方面）？我知道我需要转换日期格式以允许排序，但我是汇编新手，所以我不确定如何分解字符串以便转换它

另外，作为第二个问题，如何将数字从字符串转换为实际的数值

谢谢

---

注：我想应该注意的是，我使用的是masm32，下一个小程序是用EMU8086（16位）编写的，它从键盘上捕获数字作为字符串，将它们转换为数字进行比较，最后将数字转换为字符串进行显示。请注意，数字是用0AH捕捉的，这需要一个3级变量“str”。您需要的转换过程位于代码的底部（string2number和number2string）

现在是32位版本。接下来是一个小程序，它为EAX分配一个大数字，将其转换为字符串并将其转换回数值，如下所示：

.model small

.586

.stack 100h

.data

msj1   db 13,10,'Original EAX = $'
msj2   db 13,10,'Flipped  EAX = $'
msj3   db 13,10,'New      EAX = $'

buf    db 11
       db ?
       db 11 dup (?)

.code          
start:
;INITIALIZE DATA SEGMENT.
  mov  ax, @data
  mov  ds, ax

;CONVERT EAX TO STRING TO DISPLAY IT.
  call dollars  ;NECESSARY TO DISPLAY.
  mov  eax, 1234567890
  call number2string  ;PARAMETER:AX. RETURN:VARIABLE BUF.

;DISPLAY 'ORIGINAL EAX'.
  mov  ah, 9
  mov  dx, offset msj1
  int  21h  

;DISPLAY BUF (EAX CONVERTED TO STRING).
  mov  ah, 9
  mov  dx, offset buf
  int  21h  

;FLIP EAX.
  call dollars  ;NECESSARY TO DISPLAY.
  mov  eax, 1234567890
  call flip_eax  ;PARAMETER:AX. RETURN:VARIABLE BUF.

;DISPLAY 'FLIPPED EAX'.
  mov  ah, 9
  mov  dx, offset msj2
  int  21h  

;DISPLAY BUF (EAX FLIPPED CONVERTED TO STRING).
  mov  ah, 9
  mov  dx, offset buf
  int  21h  

;CONVERT STRING TO NUMBER (FLIPPED EAX TO EAX).
  mov  si, offset buf  ;STRING TO REVERSE.
  call string2number   ;RETURN IN EBX.
  mov  eax, ebx        ;THIS IS THE NEW EAX FLIPPED.

;CONVERT EAX TO STRING TO DISPLAY IT.
  call dollars  ;NECESSARY TO DISPLAY.
  call number2string  ;PARAMETER:EAX. RETURN:VARIABLE BUF.

;DISPLAY 'NEW EAX'.
  mov  ah, 9
  mov  dx, offset msj3
  int  21h  

;DISPLAY BUF (EAX CONVERTED TO STRING).
  mov  ah, 9
  mov  dx, offset buf
  int  21h  

;WAIT UNTIL USER PRESS ANY KEY.
  mov  ah, 7
  int  21h

;FINISH PROGRAM.
  mov  ax, 4c00h
  int  21h           

;------------------------------------------

flip_eax proc
  mov  si, offset buf  ;DIGITS WILL BE STORED IN BUF.
  mov  bx, 10 ;DIGITS ARE EXTRACTED DIVIDING BY 10.
  mov  cx, 0  ;COUNTER FOR EXTRACTED DIGITS.
extracting:       
;EXTRACT ONE DIGIT.
  mov  edx, 0 ;NECESSARY TO DIVIDE BY EBX.
  div  ebx ;EDX:EAX / 10 = EAX:QUOTIENT EDX:REMAINDER.
;INSERT DIGIT IN STRING.
  add  dl, 48 ;CONVERT DIGIT TO CHARACTER.
  mov  [ si ], dl
  inc  si
;NEXT DIGIT.
  cmp  eax, 0     ;IF NUMBER IS
  jne  extracting ;NOT ZERO, REPEAT.

  ret
flip_eax endp  

;------------------------------------------
;CONVERT STRING TO NUMBER IN EBX.
;SI MUST ENTER POINTING TO THE STRING.

string2number proc

;COUNT DIGITS IN STRING.
  mov  cx, 0
find_dollar:                                          
  inc  cx  ;DIGIT COUNTER.
  inc  si  ;NEXT CHARACTER.
  mov  bl, [ si ]
  cmp  bl, '$'
  jne  find_dollar  ;IF BL != '$' JUMP.
  dec  si  ;BECAUSE IT WAS OVER '$', NOT OVER THE LAST DIGIT.

;CONVERT STRING.
  mov  ebx, 0
  mov  ebp, 1 ;MULTIPLE OF 10 TO MULTIPLY EVERY DIGIT.
repeat:         
;CONVERT CHARACTER.                    
  mov  eax, 0 ;NOW EAX==AL.
  mov  al, [ si ] ;CHARACTER TO PROCESS.
  sub  al, 48 ;CONVERT ASCII CHARACTER TO DIGIT.
  mul  ebp ;EAX*EBP = EDX:EAX.
  add  ebx, eax ;ADD RESULT TO BX. 
;INCREASE MULTIPLE OF 10 (1, 10, 100...).
  mov  eax, ebp
  mov  ebp, 10
  mul  ebp ;AX*10 = EDX:EAX.
  mov  ebp, eax ;NEW MULTIPLE OF 10.  
;CHECK IF WE HAVE FINISHED.
  dec  si ;NEXT DIGIT TO PROCESS.
  loop repeat ;CX-1, IF NOT ZERO, REPEAT.

  ret 
string2number endp

;------------------------------------------
;FILLS VARIABLE STR WITH '$'.
;USED BEFORE CONVERT NUMBERS TO STRING, BECAUSE
;THE STRING WILL BE DISPLAYED.

dollars proc
  mov  si, offset buf
  mov  cx, 11
six_dollars:      
  mov  bl, '$'
  mov  [ si ], bl
  inc  si
  loop six_dollars

  ret
dollars endp  

;------------------------------------------
;NUMBER TO CONVERT MUST ENTER IN EAX.
;ALGORITHM : EXTRACT DIGITS ONE BY ONE, STORE
;THEM IN STACK, THEN EXTRACT THEM IN REVERSE
;ORDER TO CONSTRUCT STRING (BUF).

number2string proc
  mov  ebx, 10 ;DIGITS ARE EXTRACTED DIVIDING BY 10.
  mov  cx, 0 ;COUNTER FOR EXTRACTED DIGITS.
cycle1:       
  mov  edx, 0 ;NECESSARY TO DIVIDE BY EBX.
  div  ebx ;EDX:EAX / 10 = EAX:QUOTIENT EDX:REMAINDER.
  push dx ;PRESERVE DIGIT EXTRACTED (DL) FOR LATER.
  inc  cx  ;INCREASE COUNTER FOR EVERY DIGIT EXTRACTED.
  cmp  eax, 0  ;IF NUMBER IS
  jne  cycle1  ;NOT ZERO, LOOP. 
;NOW RETRIEVE PUSHED DIGITS.
  mov  si, offset buf
cycle2:  
  pop  dx        
  add  dl, 48 ;CONVERT DIGIT TO CHARACTER.
  mov  [ si ], dl
  inc  si
  loop cycle2  

  ret
number2string endp  

end start

---

我了解很多，但我在DD-MMM-YYYY接受我的治疗。因此，我想将DD-MMM-YYYY分解为单独的片段进行转换，以便以这种方式进行排序。要对日期进行排序，需要YYYYMMDD，因为这种格式允许您进行比较。例如，你可以用它来比较出生日期，找出谁更年轻或更老：20150514比20150502晚。对，我明白了。但日期将以DD-MMM-YYYY的形式出现，不幸的是，无法回避这一点。所以，我要做的是将其转换为YYYYMMDD、气泡排序和输出。因此，我的问题是让我在DateToNumber过程中指出正确的方向，该过程将采用DD-MM-YYYY格式parm并返回YYYYMMDD号。如果日期采用DD-MM-YYYY格式，请执行以下操作：从右到左访问所有字符，将每个字符移动到另一个字符串，忽略连字符，您将得到YYYYMMDD号，然后使用我的过程string2number对其进行转换。也许我应该这样做，让我的答案被接受^ uº：你用什么编译器进行汇编？Visual Studio？谢谢，我应该能够调整转换过程以获得所需的内容。这是有道理的。

printf

对于只将字符串传递到

ah=9/int 21h

而不查找

%d

转换或任何内容的函数来说不是一个很好的名称。也许

DOS\u put

会是一个更好的名称（尽管C

put

附加了一个换行符，这需要一个终止的

$

而不是

'\0''）。也许只要

print_string`就更好了。它绝对不是

printf

，因为

f

代表“格式化”。从最有效的数字开始计算并累加

total*=10更有效；总计+=下一位数字

。在asm中，总计可以始终保持在

AX

，并且每个循环迭代只需要一个

mul

。

.model small

.586

.stack 100h

.data

msj1   db 13,10,'Original EAX = $'
msj2   db 13,10,'Flipped  EAX = $'
msj3   db 13,10,'New      EAX = $'

buf    db 11
       db ?
       db 11 dup (?)

.code          
start:
;INITIALIZE DATA SEGMENT.
  mov  ax, @data
  mov  ds, ax

;CONVERT EAX TO STRING TO DISPLAY IT.
  call dollars  ;NECESSARY TO DISPLAY.
  mov  eax, 1234567890
  call number2string  ;PARAMETER:AX. RETURN:VARIABLE BUF.

;DISPLAY 'ORIGINAL EAX'.
  mov  ah, 9
  mov  dx, offset msj1
  int  21h  

;DISPLAY BUF (EAX CONVERTED TO STRING).
  mov  ah, 9
  mov  dx, offset buf
  int  21h  

;FLIP EAX.
  call dollars  ;NECESSARY TO DISPLAY.
  mov  eax, 1234567890
  call flip_eax  ;PARAMETER:AX. RETURN:VARIABLE BUF.

;DISPLAY 'FLIPPED EAX'.
  mov  ah, 9
  mov  dx, offset msj2
  int  21h  

;DISPLAY BUF (EAX FLIPPED CONVERTED TO STRING).
  mov  ah, 9
  mov  dx, offset buf
  int  21h  

;CONVERT STRING TO NUMBER (FLIPPED EAX TO EAX).
  mov  si, offset buf  ;STRING TO REVERSE.
  call string2number   ;RETURN IN EBX.
  mov  eax, ebx        ;THIS IS THE NEW EAX FLIPPED.

;CONVERT EAX TO STRING TO DISPLAY IT.
  call dollars  ;NECESSARY TO DISPLAY.
  call number2string  ;PARAMETER:EAX. RETURN:VARIABLE BUF.

;DISPLAY 'NEW EAX'.
  mov  ah, 9
  mov  dx, offset msj3
  int  21h  

;DISPLAY BUF (EAX CONVERTED TO STRING).
  mov  ah, 9
  mov  dx, offset buf
  int  21h  

;WAIT UNTIL USER PRESS ANY KEY.
  mov  ah, 7
  int  21h

;FINISH PROGRAM.
  mov  ax, 4c00h
  int  21h           

;------------------------------------------

flip_eax proc
  mov  si, offset buf  ;DIGITS WILL BE STORED IN BUF.
  mov  bx, 10 ;DIGITS ARE EXTRACTED DIVIDING BY 10.
  mov  cx, 0  ;COUNTER FOR EXTRACTED DIGITS.
extracting:       
;EXTRACT ONE DIGIT.
  mov  edx, 0 ;NECESSARY TO DIVIDE BY EBX.
  div  ebx ;EDX:EAX / 10 = EAX:QUOTIENT EDX:REMAINDER.
;INSERT DIGIT IN STRING.
  add  dl, 48 ;CONVERT DIGIT TO CHARACTER.
  mov  [ si ], dl
  inc  si
;NEXT DIGIT.
  cmp  eax, 0     ;IF NUMBER IS
  jne  extracting ;NOT ZERO, REPEAT.

  ret
flip_eax endp  

;------------------------------------------
;CONVERT STRING TO NUMBER IN EBX.
;SI MUST ENTER POINTING TO THE STRING.

string2number proc

;COUNT DIGITS IN STRING.
  mov  cx, 0
find_dollar:                                          
  inc  cx  ;DIGIT COUNTER.
  inc  si  ;NEXT CHARACTER.
  mov  bl, [ si ]
  cmp  bl, '$'
  jne  find_dollar  ;IF BL != '$' JUMP.
  dec  si  ;BECAUSE IT WAS OVER '$', NOT OVER THE LAST DIGIT.

;CONVERT STRING.
  mov  ebx, 0
  mov  ebp, 1 ;MULTIPLE OF 10 TO MULTIPLY EVERY DIGIT.
repeat:         
;CONVERT CHARACTER.                    
  mov  eax, 0 ;NOW EAX==AL.
  mov  al, [ si ] ;CHARACTER TO PROCESS.
  sub  al, 48 ;CONVERT ASCII CHARACTER TO DIGIT.
  mul  ebp ;EAX*EBP = EDX:EAX.
  add  ebx, eax ;ADD RESULT TO BX. 
;INCREASE MULTIPLE OF 10 (1, 10, 100...).
  mov  eax, ebp
  mov  ebp, 10
  mul  ebp ;AX*10 = EDX:EAX.
  mov  ebp, eax ;NEW MULTIPLE OF 10.  
;CHECK IF WE HAVE FINISHED.
  dec  si ;NEXT DIGIT TO PROCESS.
  loop repeat ;CX-1, IF NOT ZERO, REPEAT.

  ret 
string2number endp

;------------------------------------------
;FILLS VARIABLE STR WITH '$'.
;USED BEFORE CONVERT NUMBERS TO STRING, BECAUSE
;THE STRING WILL BE DISPLAYED.

dollars proc
  mov  si, offset buf
  mov  cx, 11
six_dollars:      
  mov  bl, '$'
  mov  [ si ], bl
  inc  si
  loop six_dollars

  ret
dollars endp  

;------------------------------------------
;NUMBER TO CONVERT MUST ENTER IN EAX.
;ALGORITHM : EXTRACT DIGITS ONE BY ONE, STORE
;THEM IN STACK, THEN EXTRACT THEM IN REVERSE
;ORDER TO CONSTRUCT STRING (BUF).

number2string proc
  mov  ebx, 10 ;DIGITS ARE EXTRACTED DIVIDING BY 10.
  mov  cx, 0 ;COUNTER FOR EXTRACTED DIGITS.
cycle1:       
  mov  edx, 0 ;NECESSARY TO DIVIDE BY EBX.
  div  ebx ;EDX:EAX / 10 = EAX:QUOTIENT EDX:REMAINDER.
  push dx ;PRESERVE DIGIT EXTRACTED (DL) FOR LATER.
  inc  cx  ;INCREASE COUNTER FOR EVERY DIGIT EXTRACTED.
  cmp  eax, 0  ;IF NUMBER IS
  jne  cycle1  ;NOT ZERO, LOOP. 
;NOW RETRIEVE PUSHED DIGITS.
  mov  si, offset buf
cycle2:  
  pop  dx        
  add  dl, 48 ;CONVERT DIGIT TO CHARACTER.
  mov  [ si ], dl
  inc  si
  loop cycle2  

  ret
number2string endp  

end start