window.onload = choosePic;

var bannerarray = new Array();
bannerarray[0]="assets/images/banner/banner3.jpg";
bannerarray[1]="assets/images/banner/banner.jpg";
bannerarray[2]="assets/images/banner/banner1.jpg";
bannerarray[3]="assets/images/banner/banner2.jpg";
bannerarray[4]="assets/images/banner/banner5.jpg";
bannerarray[5]="assets/images/banner/banner4.jpg";

var imgCount = bannerarray.length;
function choosePic() {
    if (document.images && document.getElementById('banner')) {
        var randomNum = Math.floor((Math.random() * imgCount));
        var randImage = bannerarray[randomNum];
        document.getElementById('banner').innerHTML = "<img src=\""+ randImage +"\" >";      
    }
}

function validateForm_c(formName) {  
    if(formName.firstname.value=="") {
        alert("Please enter your first name.");
        formName.firstname.focus();
        return false;
    }
    if(formName.lastname.value=="") {
        alert("Please enter your last name.");
        formName.lastname.focus();
        return false;
    }
    if(formName.phone.value=="") {
        alert("Please enter your telephone.");
        formName.phone.focus();
        return false;
    }    
    if (formName.email.value=="") {
        alert("Please enter your email address.");
        formName.email.focus();
        return false;
    }
    if(formName.company.value=="") {
        alert("Please enter your company.");
        formName.company.focus();
        return false;
    } else return checkemail(formName.email);
}
function validateForm(formName) {  
    if(formName.joinEmail.value=="") {
        alert("Please enter your email address.");
        formName.joinEmail.focus();
        return false;
    } else return checkemail(formName.joinEmail);
}
var testresults;
function checkemail(formName){  
    var str=formName.value;
    var filter=/^([\w-]+(?:\.[\w-]+)*)@((?:[\w-]+\.)*\w[\w-]{0,66})\.([a-z]{2,6}(?:\.[a-z]{2})?)$/i;
    if (filter.test(str)) testresults=true;
    else {
        alert("Please input a valid email address!");
        formName.focus();
        testresults=false;
    }
    return testresults;
}