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如何在python中突破double-while循环?

python

sdot257 · 技术社区 · 14 年前

新来的蟒蛇。如果用户选择“Q”作为“Quit”,我怎样才能跳出第二个while循环如果我按“m”,它会进入主菜单,在那里我可以停止按“Q”键。

while loop == 1:
    choice = main_menu()

    if choice == "1":
        os.system("clear")

        while loop == 1:
            choice = app_menu()

            if choice == "1":
                source = '%s/%s/external' % (app_help_path,app_version_10)
                target = '%s/%s' % (target_app_help_path,app_version_10)

            elif choice == "2":
                source = '%s/%s/external' % (app_help_path,app_version_8)
                target = '%s/%s' % (target_app_help_path,app_version_8)
            elif choice.lower() == "m":
                break
                loop = 0
            elif choice.lower() == "q":
                break
                loop = 0
            sendfiles(source, target)

    # Internal files

    elif choice == "q":
        loop = 0

应用程序菜单方法:

def app_menu()
    print "Select APP version"
    print "-------------------"
    print "1) 11"
    print "2) 10"
    print "3) 8"
    print "m) Main Menu"
    print "q) Quit"
    print
    return raw_input("Select an option: ")

6 回复 | 直到 14 年前

Aphex Bodhi Hu 14 年前

你差一点就拿到了,你只要把这两条线换一下就行了。

elif choice.lower() == "m":
    break
    loop = 0

elif choice.lower() == "m":
     loop = 0
     break

在设置 loop

Mikael S 14 年前

改变

break
loop = 0

到

loop = 0
break

S.Lott 14 年前

使用异常。

class Quit( Exception ): pass

running= True
while running:
    choice = main_menu()

    if choice == "1":
        os.system("clear")

        try:
            while True:
                choice = app_menu()

                if choice == "1":

                elif choice == "2":

                elif choice.lower() == "m":
                    break
                    # No statement after break is ever executed.
                elif choice.lower() == "q":
                    raise Quit
                sendfiles(source, target)

         except Quit:
             running= False

    elif choice == "q":
        running= False

Jack 14 年前

对两个循环使用两个不同的变量,例如 loop1 和 loop2

当你第一次在内环中按m时,你只需在外环断开,然后你可以分别处理q。

顺便说一下,你不需要内部变量来保持循环,只需要无限循环,直到按下“m”键。然后在保持第一个循环的同时从内环中脱离。

Andrew Sledge 14 年前

将top循环重命名为mainloop,并在接收到q时将mainloop设置为0。

while mainloop == 1:
    choice = main_menu()
    if choice == "1":
        os.system("clear")

        while loop == 1:
            choice = app_menu()

            if choice == "1":
                source = '%s/%s/external' % (app_help_path,app_version_10)
                target = '%s/%s' % (target_app_help_path,app_version_10)

            elif choice == "2":
                source = '%s/%s/external' % (app_help_path,app_version_8)
                target = '%s/%s' % (target_app_help_path,app_version_8)
            elif choice.lower() == "m":
                loop = 0
                break
            elif choice.lower() == "q":
                mainloop = 0break
                break
            sendfiles(source, target)

    # Internal files

    elif choice == "q":
        mainloop = 0

hughdbrown 14 年前

您可以将其放入函数并返回:

import os.path
def do_whatever():
    while True:
        choice = main_menu()

        if choice == "1":
            os.system("clear")

        while True:
            choice = app_menu()

            if choice in ("1", "2"):
                app_version = app_version_10 if choice == "1" else app_version_8
                source = os.path.join(app_help_path, app_version, "external")
                target = os.path.join(target_app_help_path, app_version)
                sendfiles(source, target)
            elif choice.lower() == "m":
                break
            elif choice.lower() == "q":
                return

诚然,我不太明白什么时候你想打破内环,什么时候你想退出两个环,但这会给你一个想法。