function assignState()
{
    var i = document.getElementById('form1').txtPostcode.value;
    if(i >= 2000 && i < 3000)
    {
        document.getElementById('form1').ddlState.value = "NSW";
    }
    else if(i >= 3000 && i < 4000)
    {
        document.getElementById('form1').ddlState.value = "VIC";
    }
    else if(i >= 4000 && i < 5000)
    {
        document.getElementById('form1').ddlState.value = "QLD";
    }
    else if(i >= 2000 && i < 3000)
    {
        document.getElementById('form1').ddlState.value = "NSW";
    }
    else if(i >= 5000 && i < 6000)
    {
        document.getElementById('form1').ddlState.value = "SA";
    }
    else if(i >= 6000 && i < 7000)
    {
        document.getElementById('form1').ddlState.value = "WA";
    }
    else if(i >= 7000 && i < 8000)
    {
        document.getElementById('form1').ddlState.value = "TAS";
    }
    else if(i >= 800 && i < 900)
    {
        document.getElementById('form1').ddlState.value = "NT";
    }
}

function openInvoice(){
alert('here');
window.open('proFormaInvoice.aspx?userID=52&reorder=10'); 

return false;

}