汇编 求字符串长度

该过程返回字符串长度到EAX寄存器中，调用该过程时需要传递字符串的偏移

INVOKE Str_length,ADDR myString

Str_length过程代码如下：

Str_length PROC USES edi,

       pString : PTR BYTE             ; pointer to string

       mov edi,pString

       mov eax,0                          ; character count

L1:  cmp byte ptr [edi],0            ; end of string?

       je L2                                  ; yes : quit

       inc edi                                ; no : point to next

       inc eax                               ; add 1 to count

       jmp L1

L2:  ret

Str_length ENDP

结果存放在eax中