data segment
string1 db ‘Please input a number:‘,0dh,0ah,‘$‘
string2 db 0dh,0ah,‘It is a number!‘,0dh,0ah,‘$‘
string3 db 0dh,0ah,‘It is not a number!‘,0dh,0ah,‘$‘
data ends
code segment
assume cs:code,ds:data
start:
mov ax,data
mov ds,ax ;初始化ds
lea dx,string1 ;取string1的偏移地址,放入dx
mov ah,09h
int 21h ;从键盘输入字符串
mov ah,01h
int 21h ;从键盘输入字符串
cmp al,30h ;和‘0’相比较
jnc GOON ;无进位转移到goon
lea dx,string3 ;取string3的偏移地址,放入dx
jmp EXIT ;跳转到exit
GOON:
cmp al,3ah ;与‘:’相比较
jnc DONE ;无进位转移到done
lea dx,string2 ;取string2的偏移地址,放入dx
jmp EXIT
DONE:
lea dx,string3 ;取string3的偏移地址,放入dx
jmp EXIT
EXIT:
mov ah,09h
int 21h ;从键盘输入字符串
mov ah,4ch
int 21h ;从键盘输入字符串
code ends
end start原文地址:http://blog.csdn.net/xuejiawei123/article/details/25339911