validationspaces.js

<script type="text/javascript">
    window.onload = function () {
        document.crear_producto.focus();
        document.crear_producto.addEventListener('submit', validarFormulario);
    }

    function validarFormulario(evObject) {
        evObject.preventDefault();
        var todoCorrecto = true;
        var formulario = document.crear_producto;
        for (var i=0; i<formulario.length; i++) {
            if(formulario[i].type =='text') {
             if (formulario[i].value == null || formulario[i].value.length == 0 || /^\s*$/.test(formulario[i].value)){
                 swal ('No puede haber campos vacíos');
                 todoCorrecto=false;
             }
         }
     }
     if (todoCorrecto ==true) {formulario.submit();}
 }
</script>