我是python的新手,我正在尝试使用raw_input和函数为程序创建一个命令。由于某种原因,它一直没有奏效。这是我一直在测试的代码:
raw_input()
def test():
print "hi, this will be amazing if it works"
答案 0 :(得分:6)
raw_input
将阻止,直到您输入内容。当收到换行符时(用户按下回车键),该值将被返回并可以存储。您似乎没有试图调用您的函数test
。也许你想尝试这样的事情(如果你需要,我可以进一步解释)
name = raw_input("What is your name: ")
def test(username):
print "Hi %s, this will be amazing if it works" % (username,)
test(name)
根据您的其他评论,这是安全的方式:
# Define two functions test() and other()
def test():
print "OMG, it works..."
def other():
print "I can call multiple functions"
# This will be to handle input for a function we don't have
def fail():
print "You gave a bad function name. I only know about %s" % (", ".join(funcs.keys()))
# This is a dictionary - a set of keys and values.
# Read about dictionaries, they are wonderful.
# Essentially, I am storing a reference to the function
# as a value for each key which is the value I expect the user to ender.
funcs = {"test": test, "other": other}
# Get the input from the user and remove any trailing whitespace just in case.
target = raw_input("Function to run? ").strip()
# This is the real fun. We have the value target, which is what the user typed in
# To access the value from the dictionary based on the key we can use several methods.
# A common one would be to use funcs[target]
# However, we can't be sure that the user entered either "test" or "other", so we can
# use another method for getting a value from a dictionary. The .get method let's us
# specify a key to get the value for, as wel as letting us provide a default value if
# the key does not exist. So, if you have the key "test", then you get the reference to
# the function test. If you have the key "other", then you get the reference to the
# function other. If you enter anything else, you get a reference to the function fail.
# Now, you would normally write "test()" if you wanted to execute test. Well the
# parenthesis are just calling the function. You now have a reference to some function
# so to call it, you have the parenthesis on the end.
funcs.get(target, fail)()
# The above line could be written like this instead
function_to_call = funcs.get(target, fail)
function_to_call()
答案 1 :(得分:3)
您需要将raw_input()的输出分配给类似的内容(documentation):
s = raw_input('--> ')
你的代码也可以工作(太棒了吗?)你刚刚定义了一个函数但没有调用它。将它添加到Python文件的末尾(没有缩进,一直到左边):
test()
答案 2 :(得分:0)
如果要使用输入,则必须将raw_input()的值赋给某些内容,如变量。
然后记住,在你调用def之前,def中的所有内容(缩进部分)都不会执行。这可能就是为什么没有任何作用,你不是在说def。
只需将test()放在某处即可调用它,然后打印出来。
在调用之前,函数不会运行。调用时执行的代码是'def'下的缩进部分。您可以将一些代码放在一个可能多次调用的函数中,而不必每次都再写一次。
答案 3 :(得分:0)
input = raw_input()
def test():
print "hi, this will be amazing if it works"
if input == "test":
test()