php - why the appended row's data didn't displayed after being submitted?

Question

this is my php code(1st page):

        <table width="600px" id="project">
            <tr>
                <td>1</td>
                <td><textarea name="pro_1" cols="100" rows="2"></textarea></td>
            </tr>
            <tr>
                <td>2</td>
                <td><textarea name="pro_2" cols="100" rows="2"></textarea></td>
            </tr>
            <tr>
                <td>3</td>
                <td><textarea name="pro_3" cols="100" rows="2"></textarea></td>
            </tr>
            <input id="addbtn" type="button" name="addbtn" value="ADD">

incorporated with javascript for append the row when button is clicked:

$("#addbtn").click(function(){
    var num=parseInt($("#project tr:last").text());
        num+=1;
            $("#project").append("<tr><td>"+num+"</td><td><textarea name='pro_"+num+"' cols='100' rows='2'></textarea></td></tr>");
                });

The 2nd page is the important page where all data from 1st page display on it:

<table width="600px" id="project">
            <tr>
                <td>1</td>
                <td><?php echo $_POST["pro_1"]; ?></td>
            </tr>
            <tr>
                <td>2</td>
                <td><?php echo $_POST["pro_2"]; ?></td>
            </tr>
            <tr>
                <td>3</td>
                <td><?php echo $_POST["pro_3"];?></td>
            </tr>
</table>

My problem is that the data of appended row didn't show on 2nd page.How to make it? The output as below:

Answer 1

On the second page do something like this:

<table width="600px" id="project">
    <?php foreach($_POST as $key => $value) { ?>
    <tr>
        <td><?php echo $key; ?></td>
        <td><?php echo $value; ?></td>
    </tr>
    <?php } ?>
</table>