<!-- This script and many more are available free online at -->
<!-- The JavaScript Source!! http://javascript.internet.com -->

<!-- Begin
function checkFields() {
missinginfo = "";
if (document.form.nombre.value == "") {
missinginfo += "\n     -  Nombre";
}
if ((document.form.email.value == "") || 
(document.form.email.value.indexOf('@') == -1) || 
(document.form.email.value.indexOf('.') == -1)) {
missinginfo += "\n     -  E-Mail";
}
if (document.form.telefono.value == "") {
missinginfo += "\n     -  Teléfono";
}
if (document.form.mensaje.value == "") {
missinginfo += "\n     -  Mensaje";
}
if (missinginfo != "") {
missinginfo ="_____________________________\n" +
"Debe escribir correctamente su:\n" +
missinginfo + "\n_____________________________" +
"\nPor favor ingrese sus datos!";
alert(missinginfo);
return false;
}
else return true;
}
//  End -->