function CmpAlta()
{

        if ((document.frmAlta.txtName.value.length == 0)  ||
            (document.frmAlta.txtDir.value.length == 0)   ||
            (document.frmAlta.txtPhone.value.length == 0) ||
            (document.frmAlta.txtFax.value.length == 0)   ||
            (document.frmAlta.txtMail.value.length == 0)  ||
            (document.frmAlta.txtContacto.value.length == 0) ||
            (document.frmAlta.txtActividad.value.length == 0) )
            {
              alert("Debe rellenar los campos obligatorios.");
            }
        else
            {
              document.frmAlta.submit();
            }
}