Working with strings

2025-11-27

LEGEND:

! ****- Required parameters

substring(str, n1, n2) - to trim a string

Parameters:

! str ****- original string

! n1 ****- number of characters to trim from the left (> 0)

n2 - number of characters to trim from the right (< 0)

endswith(str, substr) - to check if the string ends with the given substring

Parameters:

! str ****- original string - "where to search"

! substr ****- строка поиска - "what to search"

startswith(str, substr) - to check if the string starts with the given substring

Parameters:

! str ****- original string - "where to search"

! substr ****- строка поиска - "what to search"

contains(str, substr,registr) – to check if the first string contains the second string

Parameters:

! str ****- original string - "where to search"

! substr ****- строка поиска - "what to search"

registr - a flag indicating whether to consider case sensitivity (False means case should not be considered)

len(str) – to count the number of characters in a string.

Parameters:

! str ****- original string

concat(str1, str2) – to concatenate (join) the strings passed as parameters

Parameters:

! str1 ****- string 1

! str2 ****- string 2

splitter(str, s, n) - to split a string into parts. The function returns an array of elements

Parameters:

! str ****- original string

! s ****- string delimiter

n - maximum number of elements

lower(str) – to convert a string to lowercase

Parameters:

! str ****- original string

upper(str) - to convert a string to uppercase

Parameters:

! str ****- original string

strip(str) - to trim whitespace from both ends of a string

Parameters:

! str ****- original string

capitalize(str) - to replace the first character of a string with its uppercase equivalent (capitalizes the first letter of the word).

Parameters:

! str ****- original string

title(str) - to convert each word in the string str so that the first letter is uppercase and others are lowercase

normalizePhone(str) - to formate a phone number into a standard form: removes all non-digit characters and replaces the starting digit 8 with 7 if present

Parameters:

! str ****- original string with a phone number

replace(str, s1, s2, n) - to replace a substring in a string with another substring

Parameters:

! str ****- original string

! s1 ****- substring to be replaced

! s2 ****- substring to replace with

n - number of replacements

base64(str) – to encode a string in base64 format

Parameters:

! str ****- original string

base64decode(str) - to decode base64 back to a string

Parameters:

! str ****- original string

urlencode(str) - to encode a string to make it safe for HTTP transmission

Parameters:

! str ****- original string

For examle: John Smith becomes John%20Smith, а Anna&Maria becomes Anna%26Maria

urldecode(str) - to decode a URL-encoded string

Parameters:

! str ****- original string

For example: John%20Smith will be translated as John Smith

hmac_hexdigest(secret_key, msg, hash_type) - to hash a string using 'sha256', 'md5', 'sha512', or 'sha1'

Parameters:

! secret_key - key\ ! msg - string to be hashed\ ! hash_type - hash type ( 'sha256', 'md5', 'sha512' or 'sha1')

select_random(str, s) - to select a random element from a delimited string. The first parameter is the string with elements, the second is the delimiter. The second parameter defaults to '|'.

Parameters:

! str ****- original string

! s ****- string delimiter (default is '|')

Example usage:
select_random('first element | second element | another element | and another one')

tg_escape(str) - to escape a variable and display it in a Telegram message with enabled markup. The function adds a backslash before the following characters:
'_', '*', '[', ']', '(', ')', '~', '', '>', '#', '+', '-', '=', '|', '{', '}', '.', '!'

Parameters:

! str ****- original string

Let’s analyze the string trimming function: