function check_it()
{
var theurl=document.f1.t1.value;
var tomatch= /http:\/\/[A-Za-z0-9\.-]{3,}\.[A-Za-z]{3}/
if (tomatch.test(theurl)){
document.write("valid");
return true;
}else{
document.write("invalid");
return false;
}
}
URL: