使用 PHP 将 textarea 的内容保存到 .txt 文件

Question

I have a code which should save content from a text area as a text file using PHP, File is getting created if I click the button, but no data is written inside that.

Code:

           <form  method="POST" action="">
              <div data-label="Index.php" class="demo-code-preview" contentEditable="true">
                          <pre><code class="language-html">
                              <textarea name="content">
                            <?php
                              $file = "index.php";
                              echo(htmlspecialchars(file_get_contents($file)));
                              ?>
                            </textarea>
                          </code></pre>
              </div>
            </a>
              <a href="?SubmitFile=true" class="bar-anchor" name="SaveFile">
               <span>Save</span>
            <div class="transition-bar"></div>
            </a>
          </form>



<?php
if (isset($_GET['SubmitFile'])){
    $content = $_POST['content'];
    echo "<script>console.log('" . $content . "' );</script>";
    $file = "myfile.txt"; // cannot be an online resource
    $Saved_File = fopen($file, 'a+');
    fwrite($Saved_File, $content);
    fclose($Saved_File);
  }
?>

Answer 1

You are not actually submitting the form, you are only passing the SubmitFile parameter as a GET parameter when you click the link. The easiest thing to do is replace the link with a submit button, and change your PHP to look for that parameter in the POST.

If you really need to use a link to submit the form, you will need to employ some javascript to cancel the default event on the link and submit the form. In that case, you will need to add the SubmitFile parameter as a hidden field.

<form method="POST" action="">
    <div data-label="Index.php" class="demo-code-preview" contentEditable="true">
          <pre><code class="language-html">
              <textarea name="content">
            <?php
            $file = "index.php";
            echo(htmlspecialchars(file_get_contents($file)));
            ?>
            </textarea>
          </code></pre>
    </div>
    <!-- 
    This does not submit the form, it only makes a get request with the SubmitFile parameter.
    You need ot submit the form and send the SubmitFile in the post, or add the SubmitFile
    parameter to the form action if you really want to see it in the GET params.
       
    <a href="?SubmitFile=true" class="bar-anchor" name="SaveFile"><span>Save</span></a>
    -->
    <button type="submit" name="SubmitFile">Save</button>
</form>


<?php
/*
 * This will be true if the parameter is in the GET, but does not guarantee that
 * the form was posted, so you cannot rely on this as a GET parameter.
 * Change it to POST in the markup and here.
 * 
 * if (isset($_GET['SubmitFile']))
 */
if (isset($_POST['SubmitFile']))
{
    $content = $_POST['content'];
    echo "<script>console.log('" . $content . "' );</script>";
    $file       = "myfile.txt"; // cannot be an online resource
    $Saved_File = fopen($file, 'a+');
    fwrite($Saved_File, $content);
    fclose($Saved_File);
}
?>