if else 语句未正确遵循 elif [重复]

Question

我的任务是编写一个程序，该程序接受用户输入（温度），如果温度是摄氏温度，则转换为华氏温度，反之亦然。

问题在于，当您键入类似 35:C 的内容时，即使 myscale 是 C 我的代码，程序也会使用 if myscale == "F" 而不是 elif myscale == "C"：

mytemp = 0.0
while mytemp != "quit":
    info = raw_input("Please enter a temperature and a scale. For example - 75:F " \
                       "for 75 degrees farenheit or 63:C for 63 degrees celcius "\
                       "celcious. ").split(":")
    mytemp = info[0]
    myscale = str(info[1])

    if mytemp == "quit":
        "You have entered quit: "
    else:
        mytemp = float(mytemp)
        scale = myscale
        if myscale == "f" or "F":
            newtemp = round((5.0/9.0*(mytemp-32)),3)
            print "\n",mytemp,"degrees in farenheit is equal to",newtemp,"degrees in 
            celcius. \n" 
        elif: myscale == "c" or "C":
            newtemp = 9.0/5.0*mytemp+32
            print "\n",mytemp,"degrees in celcius is equal to",newtemp,"degrees in 
            farenheit. \n"
        else:
            print "There seems to have been an error; remember to place a colon (:) 
                  between "\
                  "The degrees and the letter representing the scale enter code here. "
raw_input("Press enter to exit")

Answer 1

以下内容：

    if myscale == "f" or "F":

应改为：

    if myscale == "f" or myscale == "F":

或

    if myscale in ("f", "F"):

或者（如果你的 Python 足够新，可以支持集合文字）：

    if myscale in {"f", "F"}:

同样的道理

    elif: myscale == "c" or "C":

另外，elif 后面还有一个多余的冒号。

你现在拥有的东西在语法上是有效的，但做的事情与预期的不同。

Answer 2

这是你的问题：

elif: myscale == "c" or "C":

注意elif后面的:

如其他答案所述，您还应该使用 in。