下面是将以上四个步骤整合在一起的完整代码示例: defindex_of_substring(string,substring):string_list=list(string)forindex,charinenumerate(string_list):ifchar==substring[0]:# 判断当前字符是否与子字符串的第一个字符相同ifstring[index:index+len(substring)]==substring:# 判断当前字符后续字符是否与子字符...
首先,我们需要定义一个名为String的类,该类将包含一个名为indexOf的方法。以下是实现的代码示例: classString:def__init__(self,value):self.value=valuedefindexOf(self,substring):returnself.value.find(substring) 1. 2. 3. 4. 5. 6. 在这个类中,我们首先定义了一个构造函数__init__,它接受一个字符...
sub- substring to be searched in the stringstr. startandend(optional) - substring is searched withinstr[start:end] index() Return Value If substring exists inside the string, it returns the lowest index in the string where substring is found. If substring doesn't exist inside the string, i...
Note that find() function returns the index position of the substring if it’s found, otherwise it returns -1. count() functionto find the number of occurrences of a substring in the string. s = 'My Name is Pankaj' print('Substring count =', s.count('a')) s = 'This Is The Bes...
Python Exercises, Practice and Solution: Write a Python program to determine the index of a given string at which a certain substring starts. If the substring is not found in the given string return ‘Not found’.
The index method can’t return a number because the substring isn’t there, so we get a value error instead: In order to avoid thisTraceback Error, we can use the keywordinto check if a substring is contained in a string. In the case of Loops, it was used for iteration, whereas in...
index("c")) # 2 print(string.index("z")) # error 需要明确的是函数index的输入参数为需要查找的子串,它遍历整个字符串来寻找是否包含相应的子串,如果可以找到,就返回该子串首次出现的位置。如果不存在,则将触发以下错误: ValueError: substring not found 4.2 find函数 函数find的功能和函数index的功能...
2,string.find 来进行替代 此方法与 String.indexof(substring)相似,返回 substring 在 String 第一次出现的索引位置,不出现的话返回 -1; s = "This be a string"if s.find("is") == -1:print("No 'is' here!")else:print("Found 'is' in the string.") ...
= -1:print('find one character:o')print('the first index of substring is:'+str(string.find('o')) +" position")else:print("nothing")if__name__ =='__main__': StringFormat.string_format() StringFormat.string_sub() 字符串模板方式...
' stRINg lEArn' >>> >>> str.zfill(20) #str右对齐,左边填充0 '00000000stRINg lEArn' 大小写转换 >>> str='stRINg lEArn' >>> >>> str.upper() #转大写 'STRING LEARN' >>> >>> str.lower() #转小写 'string learn' >>> >>> str.capitalize() #字符串首为大写,其余小写 ...