Python String count()函数返回给定字符串中子字符串出现的次数。

Python字符串count()

count()函数的语法为：

str.count(sub[, start[, end]])

sub是在给定字符串中找到的子字符串。

start是一个可选参数。
它指定从中查找子字符串的起始索引位置。
默认值为0。

end是一个可选参数。
它指定指定字符串中的结束索引位置。
它的默认值是字符串的长度。

让我们看一个简单的字符串count()函数示例。

s = 'I like Python programming. Python is Awesome!'

print(f'Number of occurrence of "Python" in String = {s.count("Python")}')

print(f'Number of occurrence of "Python" in String between index 0 to 20 = {s.count("Python", 0, 20)}')

输出：

Number of occurrence of "Python" in String = 2
Number of occurrence of "Python" in String between index 0 to 20 = 1

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让我们看另一个示例，在该示例中，用户将输入字符串和子字符串，我们将使用count()函数来打印出现次数。

s = input('Please enter a string:\n')

sub = input('Please enter a sub-string:\n')

print(f'Number of occurrence of "{sub}" in the "{s}" is {s.count(sub)}')

输出：

Please enter a string:
a,e,i,o,u
Please enter a sub-string:
,
Number of occurrence of "," in the "a,e,i,o,u" is 4

Please enter a string:
Hello World from Python Tutorials from theitroad
Please enter a sub-string:
from
Number of occurrence of "from" in the "Hello World from Python Tutorials from theitroad" is 2