function checkForm(form)
{
var strPostcode = form.p.value;
if ((strPostcode=="") || (strPostcode==null))
{
alert("No postcode entered, please try again");
return false;
}
if (strPostcode.length < 5)
{
alert("Invalid postcode entered, please try again");
return false;
}
strPostcode = strPostcode.toUpperCase();
var strPostcode2 = ""
var i, ch
var validChars = /[a-zA-Z0-9]/
for ( i = 0; i < strPostcode.length; i++ )
{
ch = strPostcode.charAt(i)
if ( validChars.test(ch) )
{
strPostcode2 = strPostcode2 + ch
}
}
var strIn, strOut;
strOut = strPostcode2.substring(0,strPostcode2.length-3);
strIn = strPostcode2.substring(strPostcode2.length-3);
var n, strArea, strDistrict, strSector, strUnit;
for (i = 1; i < 4; i++)
{
// Check each character in turn
// First numeric digit is start of district code
if(!isNaN(parseInt(strOut.charAt(i))))
{
strArea = strOut.substring(0, i);
strDistrict = strOut.substring(i);
break
}
}
if (i == 4)
{
alert("Invalid postcode entered, please try again");
return false
}
if (!isNaN(strArea))
{
alert("Invalid postcode entered, please try again");
return false;
}
if ((strArea.length > 2) || (strDistrict.length > 2))
{
alert("Invalid postcode entered, please try again");
return false;
}
strSector = strIn.charAt(0);
if (isNaN(strSector))
{
if (strSector == "O")
{
// The user has entered the letter "o" instead of the number zero
strSector = "0";
}
else
{
alert("Invalid postcode entered, please try again");
return false;
}
}
strUnit = strIn.substring(1);
if (!isNaN(strUnit))
{
alert("Invalid postcode entered, please try again");
return false;
}
strPostcode = strArea + strDistrict + ' ' + strSector + strUnit;
form.p.value = strPostcode;
var strTelnum = form.t.value;
if ((strTelnum != "") && (strTelnum.length < 10))
{
alert("Invalid phone number entered, please try again");
return false;
}
form.CheckNow.value = "Checking...";
return true;
}
function explain(name, msg) {
newwin = window.open('','','top=150,left=150,width=180,height=150');
if (!newwin.opener) newwin.opener = self;
with (newwin.document)
{
open();
write('');
write('' + name + ' ');
write('' + msg);
write('
Close
');
write('');
close();
}
}
function processForm()
{
if (CheckPostcode(document.CheckerForm))
{
document.CheckerForm.submit();
}
}