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JavaScript RegExp ?! Quantifier

RegExp Object Reference JavaSript RegExp Object

Definition and Usage

The ?!n quantifier matches any string that is not followed by a specific string n.

Syntax

new RegExp("regexp(?!n)")

or

/regexp(?!n)/

Example

Example

Do a global, case insensitive search for "is" not followed by " all":

var str="Is this all there is";
var patt1=/is(?! all)/gi;

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

Is this all there is

Try it yourself »

RegExp Object Reference JavaSript RegExp Object

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