python学习03——设计，与input有关

笨办法学python第36节，我写的代码如下：

from sys import exit

def rule():
    print "Congratulations! You made the right choice."
    print "But is also a terrible choice."
    print "You have to abide by the contract of the devil."
    print "Input your choice: \n 1.dog \n 2.cat \n 3. panda"

    next = raw_input("> ")

    if next.isdigit():
        next1 = int(next)
        if next1 == 1:
             print "Don't quarrel with me!"
        elif next1 == 2:
             print "Remember, good boyfriend won't quarrel with his girlfriend!"
        elif next1 == 3:
             print "Remember, don't quarrel with me!!!!!!!"
         else:
             print "Input a number in range(1,4)!"

    else:
        print "please input a number"
        exit(0)

def start():
    print "Do you want to be my boyfriend?"
    print "input 'yes' or 'no' "

    next = raw_input("> ")

    if next == "yes":
        rule()
    elif next == "no":
        print "How dare you!"
    else:
        print "You don't even know the rule, bye bye"

start()

这个用的是raw_input("> ")，下面的代码用的是input("> ")

from sys import exit

def rule():
    print "Congratulations! You made the right choice."
    print "But is also a terrible choice."
    print "You have to abide by the contract of the devil."
    print "Input your choice: \n 1.dog \n 2.cat \n 3. panda"

    next = input("> ")

    if next in range(1,4):

        if next == 1:
             print "Don't quarrel with me!"
        elif next == 2:
             print "Remember, good boyfriend won't quarrel with his girlfriend!"
        else:
             print "Remember, don't quarrel with me!!!!!!!"

    else:
        print "please input a number in range(1,4)"
        exit(0)

def start():
    print "Do you want to be my boyfriend?"
    print "input 'yes' or 'no' "

    next = raw_input("> ")

    if next == "yes":
        rule()
    elif next == "no":
        print "How dare you!"
    else:
        print "You don't even know the rule, bye bye"

start()

注：

1. 第一个代码里面：next = raw_input("> ")， 意思就是无论输入什么，都是字符串的类型，所以要在下面加上一句 next1 = int(next) 转换成数字进行判断。

2.第二个代码里面：用的 next = input("> "), 所以就不用 next.isdigit(): ，因为这个是对字符串进行的判断（参见上一节），这里的话就直接可以用 next in range(1,4):，但是应该注意的是在运行脚本的时候，如果输入字符串，要用“”引号引起来，否则会出现SyntaxError 。

3. 这两个函数均能接收字符串 ，但 raw_input() 直接读取控制台的输入（任何类型的输入它都可以接收）。而对于 input() ，它希望能够读取一个合法的 python 表达式，即你输入字符串的时候必须使用引号将它括起来，否则它会引发一个 SyntaxError 。