Python String startswith()用法及代碼示例

如果字符串以給定前綴開頭，則startswith()方法返回True，否則返回False。

用法:

str.startswith(prefix, start, end)

參數：

prefix : prefix ix nothing but a string which needs to be checked.
start : Starting position where prefix is needs to be checked within the string.
end : Ending position where prefix is needs to be checked within the string.

注意：如果未提供開始索引和結束索引，則默認情況下它將0和length-1用作開始索引和結束索引，而我們的搜索中不包含結束索引。

返回值：

It returns True if strings starts with the given
prefix otherwise returns False.

例子：

Input : text = "geeks for geeks."
        result = text.startswith('for geeks')
Output : False

Input : text = "geeks for geeks."
        result = text.startswith('geeks', 0)
Output : True

錯誤：ValueError：在目標字符串中未找到參數字符串的情況下，會引發此錯誤

# Python code shows the working of 
# .startsswith() function 
   
text = "geeks for geeks."
   
# returns False 
result = text.startswith('for geeks') 
print (result) 
   
# returns True 
result = text.startswith('geeks') 
print (result) 
   
# returns False 
result = text.startswith('for geeks.') 
print (result) 
   
# returns True 
result = text.startswith('geeks for geeks.') 
print (result)

輸出：

False
True
False
True