python - 尝试将原始输入与函数一起使用

Question

我是 python 新手，我正在尝试为具有 raw_input 和函数的程序制作一种命令。由于某种原因，它一直没有工作。这是我一直在测试的代码：

raw_input()

def test():
    print "hi, this will be amazing if it works"

Answer 1

raw_input将阻塞，直到您输入某些内容。当收到换行符（用户按回车键）时，该值将被返回并可以存储。您似乎从未尝试调用您的函数test。也许您想尝试这样的事情（如果您需要，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，这是执行此操作的安全方法：

# 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()

Answer 2

您需要将 raw_input() 的输出分配给类似的东西（文档）：

s = raw_input('--> ')

此外，您的代码确实有效（对吗？）您刚刚定义了一个函数但没有调用它。将此添加到 Python 文件的末尾（没有缩进，一直到左侧）：

test()

Answer 3

input = raw_input()

def test():
    print "hi, this will be amazing if it works"

if input == "test":
    test()

Answer 4

如果要使用输入，则必须将 raw_input() 的值分配给变量，例如变量。

然后请记住，在您调用 def 之前，您的 def（缩进部分）中的所有内容都不会执行。这可能就是为什么没有任何效果，你没有调用 def。

只需通过将 test() 放在某处来调用它，它就会打印出来。

一个函数在你调用它之前不会运行。调用时执行的代码是'def'下的缩进部分。您可以将一段代码放入可能多次调用的函数中，而不必每次都重新编写。