比較兩個字符串
1. 題目：比較字符串是否相等
2. 要求：寫一程序，比較兩個字符串String1和String2所含的字符是否相同；若相同則顯示’Match’，否則顯示’No Match’。
輸入兩個字符串之后，將串操作所必須的寄存器等參數設置好，然后使用串操作指令進行從頭到尾的比較，兩個字符串相等的條件是串長度相等且對應的字符相同。
1 ; Example assembly language program -- 2 ; Author: karllen 3 ; Date: revised 05/2014 4 5 .386 6 .MODEL FLAT 7 8 ExitProcess PROTO NEAR32 stdcall, dwExitCode:DWORD 9 10 INCLUDE io.h ; header file for input/output 11 12 cr EQU 0dh ; carriage return character 13 Lf EQU 0ah ; line feed 14 15 .STACK 4096 ; reserve 4096-byte stack 16 17 .DATA 18 str1 BYTE 80 DUP(?) 19 str2 BYTE 80 DUP(?) 20 value BYTE 11 DUP(?) 21 length1 DWORD ? 22 length2 DWORD ? 23 24 promot1 BYTE "Please Enter String1",cr,Lf,0 25 promot2 BYTE "Please Enter String2",cr,Lf,0 26 crlf BYTE cr,Lf,0 27 28 answerYes BYTE "Match",cr,Lf,0 29 answerNo BYTE "No Match",cr,Lf,0 30 PUBLIC _start ; make entry point public 31 .CODE ; start of main program code 32 _start: 33 output promot1 34 input str1,80 35 lea eax,str1 36 push eax 37 call strlen 38 add esp,4 39 mov length1,eax 40 dtoa value,eax 41 output value 42 output crlf 43 44 output promot2 45 input str2,80 46 lea eax,str2 47 push eax 48 call strlen 49 add esp,4 50 mov length2,eax 51 dtoa value,eax 52 output value 53 output crlf 54 55 mov edx,length2 56 ;;cmp String1 and String2 57 cmp eax,edx ;如果長度不相等 58 jne endCMP ;則結束 59 ;比較 60 lea esi,str1 61 lea edi,str2 62 mov ecx,length2 ;比較的長度 63 repe cmpsb 64 jz found ;比較成功則跳轉 65 66 endCMP: 67 output answerNo 68 jmp endMatch 69 found: 70 output answerYes 71 ; 72 endMatch: 73 74 INVOKE ExitProcess, 0 ; exit with return code 0 75 76 strlen PROC NEAR32 77 push ebp 78 mov ebp, esp 79 80 sub eax, eax 81 mov ebx, [ebp+8] 82 whileChar: cmp BYTE PTR [ebx], 0 83 je endWhileChar 84 inc eax 85 inc ebx 86 jmp whileChar 87 endWhileChar: 88 pop ebp 89 ret 90 strlen ENDP 91 END ; end of source code