regex example
Example 1: regex usage
regex usage examples
Example 2: python regular expression
import re
# The string you want to find a pattern within
test_string = 'Hello greppers!'
# Creating a regular expression pattern
# This is a simple one which finds "Hello"
pattern = re.compile(r'Hello')
# This locates and returns all the occurences of the pattern
# within the test_string
match = pattern.finditer(test_string)
# Outputs all the ocurrences which were returned as
# as match objects
for match in matches:
print(match)
Example 3: regex
Let regex;
regex = /d/;
regex = /D/;
regex = /S/;
regex = /s/;
regex = /w/;
regex = /W/;
regex = /b/;
These meta characters boast a pre-defined meaning and make various typical patterns easier to use.
regex= /X./;
regex= /X*/;
regex= /X+-/;
regex= /X?/;
regex=
regex=
A quantifies helps developers to define how often an element occurs.
regex = /[a-z]/;
regex = /[A-Z]/;
regex = /[e-l]/;
regex = /[F-P]/;
regex = /[0-9]/;
regex = /[5-9]/;
regex = / [a-d1-7]/;
regex = /[a-zA-Z]/;
regex = /[^a-zA-Z]/;
regex = / ^The/;
regex = / end$/;
regex = / ^The end$/;
regex = / a/;
regex = / e/;
regex = / f/;
regex = / n/;
regex = / Q…E/;
regex = / r/;
regex = / v/;
It is critical to note that escape characters are case sensitive
regex = / i/;
regex = / m/;
regex = / s/;
regex = / x/;
regex = / j/;
regex = / U/;
Example 4: regex /
str = str.replace(/\//g,'_');
Example 5: regex examples
\d matches a single character that is a digit -> Try it!\w matches a word character (alphanumeric character plus underscore) -> Try it!\s matches a whitespace character (includes tabs and line breaks). matches any character -> Try it!
Example 6: regex examples
^The matches any string that starts with The -> Try it!end$ matches a string that ends with end^The end$ exact string match (starts and ends with The end)roar matches any string that has the text roar in it