function checkEmail(email_field) {
    if (/^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/.test(email_field.value)){
        return (true)
    }
    alert("S'il vous plaît entrer une adresse e-mail valide pour continuer!")
    return (false)
}

// Blink the text in forms field
function startBlink(){
  var delayT = 750;
  var emailobj = document.getElementById("email");
  if (emailobj.value=='' || emailobj.value=='@') {
    emailobj.value = emailobj.value == '@' ? '' : '@';
    timerT = setTimeout('startBlink(' + delayT + ')', delayT);
  }
}
// Stop Blink the text in forms field on focus
function stopBlink(){
  clearInterval(timerT);
  if (document.getElementById("email").value == '@')
    document.getElementById("email").value = '';
}