如何使用if语句输入以某个字母开头的内容

发表时间：2022-07-28 00:59:11 阅读：199

如果用户输入(greet)以某个单词"hello"开头，或者如果输入以h开头，我会使用if语句打印某个输出.

我尝试过:


if greet == "hello":
    print("wrong") 
elif greet == "h_" #(but not hello)
    print(" okay")
else: 
    print("good")

🎖️ 优质答案

Nearly there but you need to do:

if greet == "hello":
    print("wrong")
elif greet[0] == "h":
    print("okay")
else:
    print("good")

In particular greet == "h_" just checks to see if the user has entered literally "h_".

也可以使用.startswith():

if greet.startswith("hello"):
    print("wrong")
elif greet.startswith("h"):
    print("okay")
else:
    print("good")

试试这个.它通过调用strip忽略前导和尾随空格，它有一个条件，表示输入中没有放置任何内容，最后它不区分大小写，因为它将输入标准化为lower:

greet = input().strip()

if len(greet) > 0:
    firstWord = greet.split(" ")[0].lower()
    if firstWord == 'hello':
        print("wrong")
    elif firstWord[0] == "h":
        print("ok")
    else:
        print("good")
else:
    print("You must enter something")