on regular expressions

[sasimca007]

Hello friends,

var x = document.frm.test.value;
var patt = new RegExp(x, "i");
var tt = 'some text';
if(tt.match(patt))
{ alert('matched'); }

In the above example it searches the first letter in x and first letter in tt matches or not i think. But what i want is if x='tr' i want to match the string in tt is starting with the value in x or not?. There is another option to do like this is

var patt = /^tr/;
var tt = 'some text';
if(tt.match(patt))
{ alert('matches'); }

By the above example we can do it when the search string we know, but the serach string is in a javascript variable, then how to do it?

[gits]

for variable regExp you need to use the 'normal' constructor like this:

[code=javascript]
var x = 'so';

var patt = new RegExp('^' + x, 'i');

var tt = 'some text';

if (patt.test(tt)) {
alert('matched' );
}
[/code]
kind regards