function validateEmpty(fld) {
    var error = "";
 
    if (fld.value.length == 0) {
        fld.style.background = 'Yellow'; 
        error = "Veuillez remplir ces champs\n"
    } else {
        fld.style.background = 'White';
    }
    return error;  
}
function trim(s)
{
  return s.replace(/^\s+|\s+$/, '');
}

function validateEmail(fld) {
    var error="";
    var tfld = trim(fld.value);                        // value of field with whitespace trimmed off
    var emailFilter = /^[^@]+@[^@.]+\.[^@]*\w\w$/ ;
    var illegalChars= /[\(\)\<\>\,\;\:\\\"\[\]]/ ;
   
    if (fld.value == "") {
        fld.style.background = 'Yellow';
        error = "Veuillez introduire votre adresse email\n";
    } else if (!emailFilter.test(tfld)) {              //test email for illegal characters
        fld.style.background = 'Yellow';
        error = "Veuillez introduire une adresse emaill correct\n";
    } else if (fld.value.match(illegalChars)) {
        fld.style.background = 'Yellow';
        error = "Votre adresse email comporte des caracteres illegaux\n";
    } else {
        fld.style.background = 'White';
    }
    return error;
}

function IsNumeric(sText)

{
   var ValidChars = "0123456789.";
   var IsNumber=true;
   var Char;

 
   for (i = 0; i < sText.length && IsNumber == true; i++) 
      { 
      Char = sText.charAt(i); 
      if (ValidChars.indexOf(Char) == -1) 
         {
         IsNumber = false;
         }
      }
   return IsNumber;
   
   }

function checkMailAlertForm(formEl)
{
	var reason = "";

  reason += validateEmpty(formEl.prenom);
  reason += validateEmpty(formEl.nom);
  reason += validateEmpty(formEl.telephone);
  reason += validateEmail(formEl.email);
  reason += validateEmpty(formEl.budget);
      
  if (reason != "")
	{
	    alert("Certains champs sont incorrect :\n" + reason);
	    return false;
  }

  if (IsNumeric(formEl.budget.value) == false)
  {
	  alert ("Veuillez donner une valeur moyenne pour le budget (pas de characteres non-numerique");
	  return false;
  }

  return true;
}