我如何从一个字符串中删除一个单词使用索引在python?

Question

我已经在字符串上使用.find()来查找用户想要从字符串中删除的单词的索引，但是现在我如何使用这个索引来删除所说的单词?

功能如下:

sentence = "The quick brown fox jumps over the lazy dog."
print("The sentence is: "+ sentence)
user_removal = input("Which word would you like to remove? ")
user_removal_word = sentence.find(user_removal)

我已经使用if语句，然后格式化，然后从句子中删除单词，然后重新创建它，但我相信有一个更好的方法来做到这一点。

Answer 1

你可以使用切片。

使用

somestring [lowerborder: upperborder]。

sentence = "The.quick.brown.fox.jumps.over.the.lazy.dog."
print("The sentence is: "+ sentence)
user_removal = input("Which word would you like to remove? ")
lowerborder = sentence.find(user_removal) -1
upperborder = lowerborder + len(user_removal) +1
firstPart = sentence[:lowerborder]
secondPart = sentence[upperborder:]
result = firstPart + secondPart
print(result)

输入:"狐狸">

输出:The.quick.brown.jumps.over.the.lazy.dog。

方法是确定两个边界，即您试图删除的单词的起始(下界)和结束(上界)的索引。

然后生成一个新字符串(firstpart)，它包含初始字符串的所有内容，直到下边界。

之后生成第二个字符串，该字符串从您要删除的单词之后开始，并包含该单词之后的所有内容。

然后把两者放在一起得到结果。单词之间的点表示输出确实只是期望的输出，因为print语句中看不到额外的空格。

Answer 2

假设句子中的单词之间用一个空格分隔。然后可以使用split()

创建所有单词的列表尝试删除指定的单词。如果单词不存在，则抛出ValueError。

如果删除成功，重新加入单词列表

sentence = "The quick brown fox jumps over the lazy dog."
print(f"The sentence is: {sentence}")
user_removal = input("Which word would you like to remove? ")
words = sentence.split()
try:
    words.remove(user_removal)
    print(' '.join(words))
except ValueError:
    print(f'Selected word "{user_removal}" is not in the sentence')

例子:

The sentence is: The quick brown fox jumps over the lazy dog.
Which word would you like to remove? jumps
The quick brown fox over the lazy dog.
The sentence is: The quick brown fox jumps over the lazy dog.
Which word would you like to remove? cat
Selected word "cat" is not in the sentence