4.asm

用汇编语言编写的在MASM上实现大小写转换,排序,比较大小的源程序和可执行文件

EXTRN  SUB1:FAR,SUB2:FAR,SUB3:FAR
PUBLIC START

HUANHANG  MACRO
          MOV DL,0DH
          MOV AH,2
          INT 21H
          MOV DL,0AH
          MOV AH,2
          INT 21H
ENDM

DATA SEGMENT
    MENU  DB '                           MENU                      $'
    MESG1 DB '1   <CHANG>   2 <MAX>   3 <SORT>    4 <TIME>    5 <EXIT>    $'
    MESG2 DB 'PLEASE INPUT THE RIGHT NUMBER:$'
    MESG3 DB 'ERROR!PLEASE INPUT THE RIGHT NUMBER AGAIN:$'         ;此处输入数据段代码 
DATA ENDS

STACK SEGMENT PARA STACK 'STACK'
      DB 100 DUP(0)
STACK ENDS

CODE  SEGMENT
      ASSUME CS:CODE,DS:DATA
START:MOV AX,DATA
      MOV DS,AX

      LEA DX,MENU            ;DISPLAY
      CALL DISP
      LEA DX,MESG1
      CALL DISP
      LEA DX,MESG2
       CALL DISP

NEXT: MOV AH,0
      INT 16H
      
      JMP PANDUAN

ERROR:MOV DL,0AH
      MOV AH,2
      INT 21H
      LEA DX,MESG3            
      CALL DISP
      JMP NEXT 
EXIT: MOV AH,4CH
      INT 21H

PANDUAN:CMP AL,31H
        JE  JUMP1
        CMP AL,32H
        JE  JUMP2
        CMP AL,33H
        JE  JUMP3
        CMP AL,34H
        JE  EXIT
        CMP AL,35H
        JE  EXIT
        JMP ERROR

JUMP1:HUANHANG
      HUANHANG
      JMP SUB1
JUMP2:HUANHANG
      HUANHANG
      JMP SUB2
JUMP3:HUANHANG
      HUANHANG
      JMP SUB3

DISP  PROC NEAR
      MOV AH,09H
      INT 21H      
      HUANHANG
      RET
DISP  ENDP          

CODE  ENDS
      END   START