var emailRe=/(^[a-z]([a-z_\.\-]*)@([a-z_\.]*)([.][a-z]{3})$)|(^[a-z]([a-z_\.]*)@([a-z_\.]*)(\.[a-z]{3})(\.[a-z]{2})*$)/i;
function can_submit_login_info(uctrl,pctrl){
    var uc=document.getElementById(uctrl);
    var pc=document.getElementById(pctrl);
    if(uc.value.length==0){
        alert('The email is empty. Please enter a valid email.');
        uc.focus(); return false;
    }
    //if(!emailRe.test(uc.value)){
    //    alert('The email is invalid. Please enter a valid email.');
    //    uc.focus(); return false;
    //}
    if(pc.value.length<4 || pc.value.length>20){
        alert('Password must be a string between 4 and 20 characters.');
        pc.focus(); return false;
    }
    return true;
}