The RegExp,$_ property represents the input to which a string is matched.
This is the same as using the input property.
<html>
<body>
<script language="JavaScript">
<!--
function getinput(){
var myPat = new RegExp("the", "i");
var str = document.form1.mytext.value;
myArray = myPat.exec(str);
alert("The RegExp.input is: " + RegExp.input);
}
-->
</script>
<form name="form1">
<br><br>
Enter some Text and click outside:
<input type="text" name="mytext" size="40" onChange='getinput()'>
<br>
</form>
</body>
</html>