Juan Isasi's questions

Hoping that everyone is doing well, I have had an inconvenience (Perhaps as a newbie) when I wanted to save information in my database from php to MySQL.

Describing the workflow of my little website.

Previously, I requested help on this page to achieve that based on a "trigger" click that would update a specific div where the information would be. I've already done that, thank you very much. Now, in a certain update of the div, I get to one where it consists of seeing some entries already made and a section to be able to make a comment, a more specific form. Basically there is only a textarea to insert the comment itself, the other data is collected from the current session and others (we will emphasize later), and a button which, in theory, is supposed to trigger a certain php code to insert the record in question.

What have I tried?

Based on the extensive php and mysql video tutorials we find all over the internet, the methodology is almost the same itself, but oddly enough, it doesn't work for me.

What I currently have in my code is the following:

<form action="" class="ejemplo" method="POST">

    <!-- <input type="text" name="respuesta"> -->
    <input type="submit" name="guardar" value="Enviar respuesta">

    <textarea name="respuesta" name="respuesta"></textarea>

    <?php 
        //if (isset($_POST['guardar'])) {
            $textor = mysqli_real_escape_string($con, $_POST['respuesta']);
            //if(empty($textor)){
                echo "<font>Introduzca algo!</font>";
            //}else{
                $fechareg = date('d-m-Y H:i:s');
                echo $fechareg;
                echo $textor;
                $sentencia = "INSERT INTO respuestas(n_control, id_pregunta, contenido, fecha) VALUES ('{$_SESSION['usuario']}','{$id}', '{$textor}', '{$fechareg}')";
                $result = mysqli_query($con, $sentencia);

            //}
        //}
    ?>

</form>

Before I clarify, you will see the if with the isset commented, since, if I ignore that validation, it DOES execute the query, but wrongly done, the user respects it, the id also, the content is blank, and the date as 0000 -00-00 00:00:00. The strange thing is also that in the echo of the variables where the date is supposed to be, it comes out fine, it is printed correctly, the text is still blank.

Now when that piece of code is executed, it prints:

Warning: Undefined array key "respuesta" in C:\xampp\htdocs\pag\ver_datos.php on line 80

As if the "answer" did not exist, but it is well raised in the form in its name. If I leave the if of isset, it just refreshes the page and does absolutely nothing, not even insert. You may also admire that it tries a simple input text and likewise it doesn't recognize it, it doesn't retrieve your text.

I heard that it can also be done through ajax, but I wouldn't know how to use it, I'm a newbie here. In the same way, do it in a separate php, but I can't find how to pass the variables such as the id.

I add the code of how the id and the user are obtained (That's right, based on what was previously selected, I get the id with post):

<?php 
    $id = $_POST['id'];
    $titulo = $_POST['titulo'];
    include("conexion.php");
    $con=conectar();
    session_start();
?>

If it is useful, I will tell you that above I receive other comments from other users. That works correctly.

Why is it that it doesn't even recognize the name of the input, and the date prints it fine but when sending it to the database it puts it in 0's? What am I doing wrong?

I have the following inconvenience: First hand, it is useful for me to specify the languages ​​that I am using:

• HTML: For the skeleton of my page.
• CSS: For the styles.
• JS: For, based on my research on the subject, whoever triggers a function to be able to update the content of my div, later I enter what I have already tried.
• PHP: To extract information from my database.
• MySQL (MariaDB with XAMPP): For the data as such.

Now, my plan is that based on touching an element that appears as a category, update a div in which the information collected from the database is. Be the following image so that you can understand me better:

In content there is something previously loaded. Already with the trigger, the other in question will be charged.

What have I tried? Based on my research on the subject, the process consists of saving the structure of the content in a separate php file and how I obtain it from the database. This structure is of the form:

//"cont-princi" es el delimitante de el area de Contenido
<aside id="cont-princi">
//"manifest-page" es un contenedor donde esta un encabezado. 
        <div id="manifest-page">
    //"title-master" es el encabezado como tal
            <div id="title-master">
                <p>Articulos recomendados</p>
            </div>
    //Un boton para cerrar sesion
            <button id="make-quest">Cerrar sesion</button>
        </div>

//Aqui obtenemos la informacion por medio de php, la conexion, consulta y demas esta arriba.
        <?php 
            while($row = mysqli_fetch_array($query)){
        ?>
//"art" es el contenedor que tiene los elementos de el articulo
            <div class="art">
//La informacion ya como tal
                <p class="titleP"><?php echo $row['titulo']?></p>
                <p class="cuerpoP"><?php echo $row['contenido'] ?></p>
            </div>
        <?php 
            }
        ?>
    </aside>

Now, for the category part, I have a JS function trigger, like this:

<div class="elemento" onclick="cargaCategoriaTal()">
    <p>Categoria Tal</p>
</div>

And then comes what I have investigated, in a JS I create the function already named and put a code that apparently must do that reload of the div in question, loading a php file. Thus:

function cargaCategoriaTal(){
    $(document).ready(function() {
        var refrescarid = setInterval(function() {
            $("#cont-princi").load("categoriaTal.php")
            .error(function() { alert("Error"); });
        }, 0); // Tiempo
        $.ajaxSetup({ cache: false });              
    });
}

Admire that we are passing the id of the div "cont-main" and also a file (which is the same level) php where the "new" content is supposed to be. In that "new" php I have, so to speak, the same structure of the content section (I will do the same for each other category), in this way:

//Note how we keep the id names the same so that they "converge" with the styles

<aside id="cont-princi">
        <div id="manifest-page">
            <div id="title-master">
                <p>Categoria 2</p>
            </div>
            <button id="make-quest">Cerrar Sesion</button>
            //Aca adentro ira lo similar que en el anterior. con algo especial de la categoria, 
//va el correspondiente codigo php
        </div>
</aside>

The detail is that it doesn't work, I detonate that method and it doesn't respond, it doesn't do anything. I have tried to put a single alert with test texts to see if it works, and yes, it shows them but it does nothing; including the "alert("Error");" of the code you investigate is not displayed. Note: I am not looking to give this time and refresh it, only that by clicking, the content div changes.

What is wrong, is there another way to do it? Or rather, how could I achieve what I'm looking for?

I thank you in advance for your answers and contributions.