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 this case it’s a conditional that can be eithertrueorfalse.It’ll be true if the substring is part of the ...
54 55 """ 56 return (sep or ' ').join(x.capitalize() for x in s.split(sep)) 57 58 59 # Construct a translation string 60 _idmapL = None 61 def maketrans(fromstr, tostr): 62 """maketrans(frm, to) -> string 63 64 Return a translation table (a string of 256 bytes long) ...
ValueError: substring not found >>> str.index("n") #同find类似,返回第一次匹配的索引值 4 >>> str.rindex("n") #返回最后一次匹配的索引值 11 >>> str.count('a') #字符串中匹配的次数 0 >>> str.count('n') #同上 2 >>> str.replace('EAR','ear') #匹配替换 'string learn' >...
print(main_string[0]) # Index 1 print(main_string[1]) # Check if Index 1 is whitespace print(main_string[1].isspace) # Slicing 1 print(main_string[0:11]) # Slicing 2: print(main_string[-18:]) # Slicing and concatenation print(main_string[0:11] +". "+ main_string[-18:]) ...
empty_string = '' # Also an empty string second_empty_string = "" # We are not done yet third_empty_string = """ # This is also an empty string: ''' 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15.
rindex('o', 8)) # ValueError: substring not found 性质判断 可以通过字符串的startswith、endswith来判断字符串是否以某个字符串开头和结尾;还可以用is开头的方法判断字符串的特征,这些方法都返回布尔值,代码如下所示。 s1 = 'hello, world!' print(s1.startswith('He')) # False print(s1.startswith...
if file_p.find('一直会被删除的') != -1 and os.path.exists(file_path): os.remove(file_p) 1. 2. 字符串开头、结尾 startswith() \endwith() 有时候确定 某字符串是否以某子字符串为开头、结尾,就要用到startswith()、 endswith(); ...
main_string = "I learned English and Python with ZHouluobo. You can do it too!" # Index 0 print(main_string[0]) # Index 1 print(main_string[1]) # Check if Index 1 is whitespace print(main_string[1].isspace()) # Slicing 1 print(main_string[0:11]) # Slicing 2: print(main_...
<bool> = in <str> # Checks if string contains the substring. <bool> = <str>.startswith() # Pass tuple of strings for multiple options. <int> = <str>.find() # Returns start index of the first match or -1. <int> = <str>.index() # Same, but raises ValueError if there's ...
<bool> = in <str> # Checks if string contains a substring. <bool> = <str>.startswith() # Pass tuple of strings for multiple options. <bool> = <str>.endswith() # Pass tuple of strings for multiple options. <int> = <str>.find() # Returns start index of first match or -1....