function set_order_by(form_id, column, default_way) {

var form_obj  = document.getElementById(form_id);
var order_way = (default_way!=undefined) ? default_way:'ASC';

if (form_obj.order_by.value.indexOf(column)!=-1) {
    if (form_obj.order_by.value==('ORDER BY '+column+' ASC')) {
        form_obj.order_by.value = 'ORDER BY '+column+' DESC';
        }
    else {
        form_obj.order_by.value = 'ORDER BY '+column+' ASC';
        }
    }
else {
    form_obj.order_by.value = 'ORDER BY '+column+' '+order_way;
    }

form_obj.submit();
}


function set_field(form_id, field, value, submit) {

var form_obj = document.getElementById(form_id);
eval('form_obj.'+field+'.value = value');

if (submit) {
    submit_form(form_id);
    }
}


function submit_form(form_id) {

var form_obj = document.getElementById(form_id);
form_obj.submit();
}


function set_dropdown_value(form_id, field, value, submit) {

var form_obj = document.getElementById(form_id);
var select_obj = eval('form_obj.'+field);
var found = false;
var i=0;

while (i<select_obj.options.length && !found) {
    if (select_obj.options[i].value==value) {
        select_obj.selectedIndex = i;
        found = true;
        }
    i++;
    }

if (submit) {
    submit_form(form_id);
    }
}


function is_valid_email(str) {

var email_structure = /^([a-zA-Z0-9\.\-\_]+)\@(([a-zA-Z0-9\-]+\.)+([a-zA-Z0-9\-]+))$/;
var is_email = false;

is_email = str.match(email_structure);

return is_email;
}