Regular Expression To Find Single Apersands In Text

Regular Expression To Find Single Apersands In Text

22nd September 2008 - 2 minutes read time

Encoding special characters in a block of HTML or other code can be a pain because there might already be ampersands there that impart encoding. This might be an ampersand that has already been encoded with a &, or it might be an ampersand in the code as an if statement or similar.

Use the following regular expression to find any ampersand that hasn't already been encoded.

([^&])&(?!#?[a-zA-Z0-9]{2,6};|\$|&)

When using replace, you can turn any ampersand into & by using the following replace.

$1&

The only problem with this statement is when the code uses a & operator as part of a statement to do bitwise operations.

Regular Expressions

Add new comment

The content of this field is kept private and will not be shown publicly.
CAPTCHA
1 + 1 =
Solve this simple math problem and enter the result. E.g. for 1+3, enter 4.
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.

Related Content

Common Regular Expressions

24th March 2008

Here are some of the regular expressions that I frequently use.

Find a blank line

^$

Spaces

[ \t]+

You can use this to break a text string apart into words.

Date

Read more

RegExLib.com: The Regular Expression Library

22nd March 2008

Writing regular expressions can sometimes be a real pain, especially if you are not used to them. Rather than trying for yourself to make a regular expression you might want to think about looking for regular expressions that other people have made.

Read more

reWork: A Regular Expression Workbench

21st March 2008

Regular expressions are a very useful tool for any programmer wanting to validate input, format strings, change words, reformat data or even split apart a string into an array.

Read more