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JavaScript leftContext Property

RegExp Object Reference Complete RegExp Object Reference

Definition and Usage

The leftContext property is the substring in front of the characters most recently matched.

This property contains everything from the string from before the match.

Syntax

RegExp.leftContext

Example

In the following example we will see the text from the string in front of the last match:

<script type="text/javascript">

var str = "The rain in Spain stays mainly in the plain";
var patt1 = new RegExp("ain");

patt1.test(str);
document.write("Text before match: " + RegExp.leftContext);
</script>

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RegExp Object Reference Complete RegExp Object Reference

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