Assuming your string is s:
'$' in s # found
'$' not in s # not found
# original answer given, but less Pythonic than the above...
s.find('$')==-1 # not found
s.find('$')!=-1 # found
And so on for other characters.
... or
pattern = re.compile(r'[\d\$,]')
if pattern.findall(s):
print('Found')
else:
print('Not found')
... or
chars = set('0123456789$,')
if any((c in chars) for c in s):
print('Found')
else:
print('Not Found')
GeeksforGeeks
geeksforgeeks.org › python › python-check-if-string-contains-character
Check if string contains character - Python - GeeksforGeeks
July 23, 2025 - Explanation: The in operator is ... found!", otherwise, it prints "Character not found!". find() method searches for a character in a string and returns its index....
Python Examples
pythonexamples.org › python-check-if-string-contains-specific-character
Python - Check if String contains Specific Character
In the following program, we will take a string name, and check if the string contains the character 'a'. x= 'apple' ch = 'a' if ch in x : print('The character is present in string.') else : print('The character is not present in string.') The character is present in string.
python - How to check a string for specific characters? - Stack Overflow
How can I check if a string has several specific characters in it using Python 2? For example, given the following string: The criminals stole $1,000,000 in jewels. How do I detect if it has dollar More on stackoverflow.com
check whether a string contains a character in python - Stack Overflow
I am trying to compare and see if a particular character exists in the string, but when i try to access the character which is in another string, its throws an error 'argument of type 'int' is not More on stackoverflow.com
How can you check if a string contains any one character from a set of characters?
Read this: https://stackoverflow.com/questions/19859282/check-if-a-string-contains-a-number More on reddit.com
10
3
May 24, 2022How to check if a string contains a character in a list
Use a loop , iterate through the list, check for existence of the character . More on reddit.com
7
3
February 19, 202201:26
How To Check If A String Only Has Letters In Python - YouTube
03:47
Check If A String Contains All Unique Characters | Python Example ...
15:15
How To Check A String For A Character In Python - YouTube
08:20
How to check if a string contains a substring in Python | Python ...
How to Find in String using Python | String Contains Substring ...
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Check if a Python String Contains a Substring (Overview) (Video) ...
O'Reilly
oreilly.com › library › view › python-cookbook › 0596001673 › ch03s07.html
Checking Whether a String Contains a Set of Characters - Python Cookbook [Book]
July 19, 2002 - The solution generalizes to any sequence (not just a string), and any set (any object in which membership can be tested with the in operator, not just one of characters): def containsAny(str, set): """ Check whether sequence str contains ANY of the items in set.
Authors: Alex MartelliDavid Ascher
Published: 2002
Pages: 608
Quora
quora.com › How-do-I-check-if-a-string-contains-a-character-in-Python
How to check if a string contains a character in Python - Quora
Quora is a place to gain and share knowledge. It's a platform to ask questions and connect with people who contribute unique insights and quality answers.
Top answer 1 of 9
356
Assuming your string is s:
'$' in s # found
'$' not in s # not found
# original answer given, but less Pythonic than the above...
s.find('$')==-1 # not found
s.find('$')!=-1 # found
And so on for other characters.
... or
pattern = re.compile(r'[\d\$,]')
if pattern.findall(s):
print('Found')
else:
print('Not found')
... or
chars = set('0123456789$,')
if any((c in chars) for c in s):
print('Found')
else:
print('Not Found')
2 of 9
35
user Jochen Ritzel said this in a comment to an answer to this question from user dappawit. It should work:
('1' in var) and ('2' in var) and ('3' in var) ...
'1', '2', etc. should be replaced with the characters you are looking for.
See this page in the Python 2.7 documentation for some information on strings, including about using the in operator for substring tests.
Update: This does the same job as my above suggestion with less repetition:
# When looking for single characters, this checks for any of the characters...
# ...since strings are collections of characters
any(i in '<string>' for i in '123')
# any(i in 'a' for i in '123') -> False
# any(i in 'b3' for i in '123') -> True
# And when looking for subsrings
any(i in '<string>' for i in ('11','22','33'))
# any(i in 'hello' for i in ('18','36','613')) -> False
# any(i in '613 mitzvahs' for i in ('18','36','613')) ->True
Codecademy
codecademy.com › article › how-to-check-if-a-string-contains-a-substring-in-python
How to Check if a String Contains a Substring in Python | Codecademy
Since the substring is present in the string and it starts from index 17, the code produces this output: ... Let’s move on to the next method on the list, which is the Python .contains() method. In Python, the .contains() method in the operator module offers the same functionality as the in operator but in a function form. This can be specifically useful in scenarios where we need to pass the containment logic as a callable. For example, when working with higher-order functions like filter(), or when designing functional-style code that requires operations to be expressed as functions rather than operators.
Real Python
realpython.com › python-string-contains-substring
How to Check if a Python String Contains a Substring – Real Python
September 10, 2025 - In this code snippet, you’ve used the same pattern that you used earlier to match only words that contain secret but then continue with one or more word character (\w+). Only one of the companies in this fake dataset seems to operate secretly! You can write any complex regex pattern and pass it to .str.contains() to carve from your pandas column just the rows that you need for your analysis. Now that you know how to check if Python string contains a substring, you can use the questions and answers below to check your understanding and recap what you’ve learned.
DigitalOcean
digitalocean.com › community › tutorials › python-string-contains
Python String contains | DigitalOcean
Learn how to check if one Python string contains another using the contains () method. This case-sensitive instance method returns True or False based on …
Top answer 1 of 2
3
Your problem is on this line:
holderString = 0
You reassigned the holderString variable to the integer 0. While strings can be iterated over, integers cannot. You attempt to iterate over the new integer on this line:
if s[i] not in holderString:
which causes the error.
There is a much better way to approach a function that returns the first repeated character though. Simply use the index() method:
def findChar(char, string):
for c in string:
if c == char:
return string.index(c)
2 of 2
0
It appears you only need to count unique characters until you find the first duplicate. You can do that with a set.
def longest_substring(s: str) -> int:
seen = set()
for c in s:
if c in seen:
break
seen.add(c)
return len(seen)
LearnDataSci
learndatasci.com › solutions › python-string-contains
Python String Contains – See if String Contains a Substring – LearnDataSci
Of the three options listed in this article, using if ... in is usually the best approach for seeing if a string contains a substring. Remember that the simplest solution is quite often the best one! Another option you've got for searching a string is using the find() method. If the argument we provide find() exists in a string, then the function will return the start location index of the substring we're looking for. If not, then the function will return -1. The image below shows how string characters are assigned indexes:
EyeHunts
tutorial.eyehunts.com › home › python string contains character
Python string contains the character
April 8, 2024 - The easiest way to check if a Python string contains a character is to use the in operator. It returns a Boolean (either True or False) Simple example code.
Javatpoint
javatpoint.com › check-if-string-has-character-in-python
Check if String has Character in Python - Javatpoint
Check if String has Character in Python with tutorial, tkinter, button, overview, canvas, frame, environment set-up, first python program, etc.
DataCamp
datacamp.com › tutorial › python-string-contains
Python String Search and Replace: in, .find(), .index(), .count(), and .replace() | DataCamp
March 31, 2026 - Python’s text strings are Unicode. Substring operations are case-sensitive by default and implemented in C for speed. The most direct way to test if text appears inside a string is the in operator, which returns a Boolean using the string’s __contains__() implementation.
AskPython
askpython.com › python › string › python-string-contains
Python String contains: Check if String Contains Substring - AskPython
April 27, 2023 - Let’s look at some examples of how to check whether a string contains a substring in Python. str = "Hello World!" sub_str = "World" if (str.__contains__(sub_str)): print("String contains Substring") else: print("String does not contain Substring") ...
Spark By {Examples}
sparkbyexamples.com › home › python › python string contains
Python String Contains - Spark By {Examples}
May 31, 2024 - In this article, we will discuss different ways to check whether the given substring exists in the string or not. 1. Quick Examples of string contains
iO Flood
ioflood.com › blog › python-string-contains
Python String Contains | Methods and Usage Examples
December 5, 2023 - In this example, ‘Python is fun!’ is a string. We’ve assigned this string to the variable sentence and then printed it. A substring is a part of a string. It could be the entire string, just one character, or any number of consecutive characters from the string.
Replit
replit.com › home › discover › how to check if a string contains certain characters in python
How to Check a String for Characters in Python | Replit
April 14, 2026 - Learn how to check if a Python string contains certain characters. We cover methods, tips, real-world uses, and common error debugging.
Metaschool
metaschool.so › home › software development › master string searches in python 2025
Master String Searches in Python 2025
February 7, 2025 - A substring is a sequence of characters that appears within another string. It is a contiguous segment of the original string, meaning the characters are adjacent and in the same order. For example, in the string "hello", "ell" and "lo" are ...
ReqBin
reqbin.com › code › python › wzo2s8ib › python-string-contains-example
How to check if a string contains a substring in Python?
December 20, 2022 - To check if a Python string contains the desired substring, you can use the "in" operator or the string.find() method.
Reddit
reddit.com › r/learnpython › how can you check if a string contains any one character from a set of characters?
r/learnpython on Reddit: How can you check if a string contains any one character from a set of characters?
May 24, 2022 -
Is there some easy, built-in way to check if a given string contains at least one single digit, 0-9? Everything I'm searching talks about the in operator or the find method, but those seem to require that you already know which digit you are looking for.
I'm leaning toward using an RE, but I wanted to know if there was a simpler way first.
Examples that would evaluate to true would be:
'44 a b' 'aa ba 5' '45 187'
and false would be any string without at least one digit.
I figure I can just try to match it with \d+, but I don't want to rely on REs too much, even though I find them fun!
Thanks!
Top answer 1 of 4
4
There's str.isdigit() checking if a string contains digits only: >>> '44 a b'.isdigit() False >>> Combined with any, applied to each character: >>> any([c.isdigit() for c in "44 a b"]) True >>>
2 of 4
3
Returns True if there is a digit and False if no digit: >>> not set('44 a a b').isdisjoint('1234567890') True >>> not set('testing').isdisjoint('1234567890') False >>> or >>> bool(set('3 a a b') & set('1234567890')) True >>> bool(set('testing') & set('1234567890')) False >>>