From http://www.w3schools.com (Copyright Refsnes Data)

JavaScript RegExp \B Metacharacter

RegExp Object Reference JavaScript RegExp Object

Definition and Usage

The \B metacharacter is used to find a match not at the beginning or end of a word.

If no match is found, it returns null.

Syntax

new RegExp("\Bregexp")

or simply:

/\Bregexp/

Example

Example

Do a global search for "Schools" NOT at the beginning or end of a word in a string:

var str="Visit W3Schools";
var patt1=/\School/g;

The marked text below shows where the expression gets a match:

Visit W3Schools

Try it yourself »

RegExp Object Reference JavaScript RegExp Object

From http://www.w3schools.com (Copyright Refsnes Data)