What is regular expression ?
Regular expression originating from the Unix system . where a program was designed , called grep. To help the developers to work on string and manipulate the strings.
Regular expression is search for a pattern in a given string or text. these search pattern written using a special format which a regular expression parser understand.
Regular expression is a very useful tool for developers, they allow to find , identify or replace text, word or any kind of character.
Regular expression is also called REGEX or REGEXP.
Regular expression syntax
Regular Expression Will match
1) Foo this is a string, the string “foo”
2) ^foo “foo” at the start of a string
3) Foo$ “foo” at he end of a string
4) ^foo$ “foo” when it is alone on a string
5) [abc] a,b, or c
6) [a-z] any lower case leter
7) [^A-Z] any character that is not uppercase letter
8) (gif|jpeg) matches either gif or jpeg
9) [a-z]+ one or more lowercase letters
10) [0-9.-] any numbers, dot or minus sign
11) ^[a-zA-Z0-9_]{1,}$ any word of at least 1 letter, number or underscore
12) ([wx])([yz]) wy, wz, xy, or xz
13) [^a-zA-Z0-9] any symbols but not any letter or number
14) ([A-Z]{3}|[0-9]{4}) Matches three letters or four numbers
a
Dont Forget to leave Your comments...
Part 2 will coming soon.....
0 comments:
Post a Comment