Regular Expression Basic Characters

 

Regular Expressions use punctuation characters to tell the system what to do when looking for something. These characters can call different behaviors, like:

  • Find a specific character
  • Look for this particular thing and make sure it's not targeted
  • Something within this range

 

By using basic characters in regular expressions, you can:

 

  • Achieve a wide range of usability to validate expressions
  • Keep your code crisp and clean as well as get faster validation of expressions

 

Here's a list of the things you'll be using most often:

Common Regex Characters

 

Character Pattern Name Description
. Period Matches any character
x* Star/Asterisk Matches zero or more of the preceding character (in this case, x)
.* Period-Star Matches any number of any character (anything, basically!)
x+ Plus Matches one or more of the preceding characters (in this case, x)
\ Backslash The next character is to be treated differently or "escaped."
x? Question Mark Preceding character is optional. Matches zero or one occurrence
\d Escape-d Matches any single digit (0-9)
\w Escape-w Matches any word character (letters, numbers, and underscore)
x|y Or pipe Matches x OR y
(hats?|scar(f|ves)) Parentheses

Groups specific items together. This example will match

hat, hats, scarf, scarves
 
[xyz] Brackets Specify ranges of letters and numbers

 

Please see this Note on Regular Expression Characters for additional information.

 

 

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