用户验证登录程序的实现

实验3.3.8用户验证登录程序的实现程序执行后，给出操作提示，请用户键入用户名和密码；.486DATASEGMENTUSE16MESG1DB'请输入用户名:',0DH,0AH,'$'MESG2DB0DH,0AH,'请输入密码:',0DH,0AH,'$'MESG3DB'欢迎进入DOS系统!$'MESG4DB0DH,0AH,'---ERROR!$'BUF1DB'1'LLLEQU$-BUF1BUF2DB'2'MMMEQU$-BUF2BUF3DB15DB?DB15DUP(?)BUF4DB15DUP(?)DATAENDSCODESEGMENTUSE16ASSUMECS:CODE,DS:DATABEG:MOVAX,DATAMOVDS,AXMOVAH,9MOVDX,OFFSETMESG1INT21H;显示用户名输入界面MOVAH,0AHMOVDX,OFFSETBUF3INT21H;键入用户名MOVBX,OFFSETBUF1MOVSI,OFFSETBUF3+2MOVCX,LLLNEXT1:MOVAL,[BX]CMP[SI],ALJNZEXITINCSIINCBXLOOPNEXT1;比较BUF1和BUF3MOVAH,9MOVDX,OFFSETMESG2INT21H;显示密码输入界面MOVCX,MMMMOVSI,OFFSETBUF4NEXT2:MOVAH,7INT21HMOV[SI],ALINCSILOOPNEXT2;将密码键入BUF4MOVCX,MMMMOVBX,OFFSETBUF2MOVSI,OFFSETBUF4NEXT3:MOVAL,[BX]CMP[SI],ALJNZEXITINCSIINCBXLOOPNEXT3;比较BUF2和BUF4MOVAH,9MOVDX,OFFSETMESG3INT21HJMPLASTEXIT:MOVAH,9MOVDX,OFFSETMESG4INT21HLAST:MOVAH,4CHINT21HCODEENDSENDBEG