文件上传验证问题 PHP

Issue with file uploads validation PHP

我在这方面一直遇到断断续续的问题。这是非常不一致的。我有一个表格,其中有标题(输入)、简短描述(输入)、完整描述(文本区域)和图像上传。 (以下所有相关代码)。

在表单上按下提交后,PHP 脚本会 运行 处理文件上传。在将每个文件从其临时位置移动之前,它会通过一系列 if 语句进行验证。如果验证阶段失败,则应用该条件的 else 语句,并根据问题将 PHP session、'reason' 设置为一个词。 (即 $_SESSION['reason']="invalidfile')。然后用户将被重定向回表单页面,根据 'reason' 的设置,用户会看到一个特定的错误。该第一个验证条件有效(检查所有字段是否已填写)。但是,none 其中在那个之后有效。除了有时它们确实有效。

如能就此问题提供任何帮助,我们将不胜感激。了解有时在 Chrome 中上传图像但页面永远不会进一步重定向到确认页面也可能很有用。这在 Microsoft Edge 中永远不会发生。

HTML 表格 - 标题、简短说明、完整说明、图像文件

// If there is a file uploaded when you redirect back from the confirm page and 'return' is set in the header.
  if(isset($_SESSION['file'])){
    // For every image uploaded:
    for($i = 0; $i < count($_SESSION['file']['destination']); $i++){
      // Delete the image because the user is forced to reupload them anyway.
      unlink($_SESSION['file']['destination'][$i]);
    }

    // Unset the 'file' session now we don't need it anymore
    unset($_SESSION['file']);
    header("Location: index.php?page=createproject");
  }
?>

<h1>Create Project</h1>
<p><a href="index.php?page=admin">Go back</a></p>

<form action="index.php?page=createprojectstorefiles" method="post" enctype="multipart/form-data">
  <p>Project Title: <input type="text" name="title" maxlength="35" autocomplete="off"
    <?php
    if(isset($_SESSION['project_details'])){
      echo "value='".$_SESSION['project_details']['title']."'";
    }
    ?>
    /></p>
  <p>Project Images: <input type="file" name="file[]" accept=".png, .jpg, .jpeg" multiple/></p>
  <p><label for="textarea" style="vertical-align: top; margin-right: 5px;">Short Descritption: </label><textarea name="short_description" rows="4" cols="60" maxlength="80" style="resize: none;"><?php
      if(isset($_SESSION['project_details'])){
        echo $_SESSION['project_details']['short_description'];
      }
    ?></textarea></p>
  <p><label for="textarea" style="vertical-align: top; margin-right: 5px;">Full Story: </label><textarea name="long_description" rows="15" cols="125" maxlength="5000" style="resize: none;"><?php
      if(isset($_SESSION['project_details'])){
        echo $_SESSION['project_details']['long_description'];
      }
    ?></textarea></p>

  <?php
    // If a reason has been sent for the form not working and the user hasn't been logged out.
    if(isset($_SESSION['reason'])){

      // If a 'reason' has been sent for not logging in.
      if(isset($_SESSION['reason'])){

        // Tell the user the reason.
        if($_SESSION['reason']=="noinput"){
          echo "<p><font color='red'><span class='error'>You can't leave any boxes blank</span></font></p>";
        } elseif($_SESSION['reason']=="invalidfile"){
          echo "<p><font color='red'><span class='error'>The file must be a '.jpg', '.jpeg' or '.png'</span></font></p>";
        } elseif($_SESSION['reason']=="uploaderror"){
          echo "<p><font color='red'><span class='error'>There was an error uploading your image!</span></font></p>";
        } elseif($_SESSION['reason']=="filetoolarge"){
          echo "<p><font color='red'><span class='error'>Your file is too large. The max file size is 500MB</span></font></p>";
        } elseif($_SESSION['reason']=="success"){
          header("Location: index.php?page=createprojectconfirm");
        } else{
          echo "<p><font color='red'><span class='error'>Something went wrong in validation, contact a network administrator</span></font></p>";
        }

        // Once the user has been told, unset the session.
        unset($_SESSION['reason']);

      // Otherise, presume that it's due to an incorrect username or password.
      } else{
        echo "<p><font color='red'><span class='error'>Something went wrong in validation, contact a network administrator</span></font></p>";
      }
    }
  ?>

  <p><button type="reset">Reset Form</button> <button type="submit" name="createproject">Preview Project</button></p>
</form>

PHP 脚本 - 验证并从临时文件夹移动上传的文件

    // Make sure no reason is set.
  if(isset($_SESSION['reason'])){
    unset($_SESSION['reason']);
  }

  if(isset($_SESSION['file'])){
    unset($_SESSION['file']);
  }

  // If the create project form has been submitted:
  if(isset($_POST['createproject'])){

    // Set all of the variables for the other text boxes in a session called 'project_details'.
    $_SESSION['project_details']['title'] = $_POST['title'];
    $_SESSION['project_details']['short_description'] = $_POST['short_description'];
    $_SESSION['project_details']['long_description'] = $_POST['long_description'];

    // If all of the fileds have been filled in:
    if(!empty($_POST['title']) && $_FILES['file']['error'][0]=='UPLOAD_ERR_OK' && !empty($_POST['short_description']) && !empty($_POST['long_description'])){

      // Count the number of files uploaded.
      $fileCount = count($_FILES['file']['name']);
      $_SESSION['file']['count'] = $fileCount;

      // Do for every uploaded file.
      for($i = 0; $i < $fileCount; $i++){

        // Set all of the variables for the file upload (file $i).
        $file = $_FILES['file'];

        $_SESSION['file']['name'] = $_FILES['file']['name'][$i];
        $_SESSION['file']['tmpName'] = $_FILES['file']['tmp_name'][$i];
        $_SESSION['file']['size'] = $_FILES['file']['size'][$i];
        $_SESSION['file']['error'] = $_FILES['file']['error'][$i];
        $_SESSION['file']['type'] = $_FILES['file']['type'][$i];

        $fileExt = explode(".", $_SESSION['file']['name']);
        $_SESSION['file']['actualExt'] = strtolower(end($fileExt));

        $allowed = array("jpg", "jpeg", "png");

        // If the file type is allowed:
        if(in_array($_SESSION['file']['actualExt'], $allowed)){

          // If there was no error uploading the file:
          if($_SESSION['file']['error'] == 0){

            // If the file isn't too large:
            if($_SESSION['file']['size'] < 500000){

              // Move the file from the temporary location to the new destination and set $_SESSION['reason'] to success so the page redirects to the confirm page. This shouldn't have to be neccesary to make it work but it is. No body on earth knows why.
              $fileNameNew = uniqid("", true).".".$_SESSION['file']['actualExt'];
              $_SESSION['file']['destination'][$i] = "projects/uploads/".$fileNameNew;
              move_uploaded_file($_SESSION['file']['tmpName'], $_SESSION['file']['destination'][$i]);

          // Otherwise, inform the user.
            } else{
              for($i = 0; $i < count($_SESSION['file']['destination']); $i++){
                // Delete the image because the user is forced to reupload them anyway.
                unlink($_SESSION['file']['destination'][$i]);
              }

              $_SESSION['reason']="filetoolarge";
              header("Location: index.php?page=createproject");
              exit();
            }

          // Otherwise, inform the user.
          } else{
            for($i = 0; $i < count($_SESSION['file']['destination']); $i++){
              // Delete the image because the user is forced to reupload them anyway.
              unlink($_SESSION['file']['destination'][$i]);
            }

            $_SESSION['reason']="uploaderror";
            header("Location: index.php?page=createproject");
            exit();
          }

        // Otherwise, inform the user.
        } else{
          for($i = 0; $i < count($_SESSION['file']['destination']); $i++){
            // Delete the image because the user is forced to reupload them anyway.
            unlink($_SESSION['file']['destination'][$i]);
          }

          $_SESSION['reason']="invalidfile";
          header("Location: index.php?page=createproject");
          exit();
        }
      }

      // After all the files have been uploaded, if the header function doesn't work, use the session method to redirect to the complete page.
      if(!header("Location: index.php?page=createprojectconfirm")){
        $_SESSION['reason']="success";
        exit();
      }

    // Otherwise, inform the user.
    } else{
      $_SESSION['reason']="noinput";
      header("Location: index.php?page=createproject");
      exit();
    }
  } else{
    header("Location: index.php?page=admin");
    exit();
  }

问题出在第一段代码上。如果用户从预览页面 returned,顶部有一个 if 语句来取消设置会话 'file'。这包含加载页面时设置 if 'file' 的条件。这种情况也可能不仅存在于用户 return 从预览页面编辑时,因为他们选择这样做,而且如果出现错误。此 if 语句然后重新加载页面,从而清除 'reason' 会话并且错误不显示。

我通过编辑 if 语句的条件修复了它。通过添加检查以确保未设置 'reason' 会话,即没有错误,但用户选择了 return:

if(isset($_SESSION['file']) && !isset($_SESSION['reason'])){
    // For every image uploaded:
    for($i = 0; $i < count($_SESSION['file']['destination']); $i++){
      // Delete the image because the user is forced to reupload them anyway.
      unlink($_SESSION['file']['destination'][$i]);
    }

    // Unset the 'file' session now we don't need it anymore
    unset($_SESSION['file']);
    header("Location: index.php?page=createproject");
  }