Php 在Codeigniter 3中上载时，如何显示不允许的文件类型错误消息？

我正在使用Codeigniter 3.1.8和Bootstrap 4开发一个基本的

当然，这些帖子都有主要的图像。如果用户没有上传图像，则会有一个默认图像，但如果上传图像，则只允许3种类型：jpg、jpeg和png

为了在用户试图上传其他文件格式时警告用户，我在Posts控制器中这样做：

// Upload image
$config['upload_path'] = './assets/img/posts';
$config['allowed_types'] = 'jpg|jpeg|png';
$config['max_size'] = '2048';

$this->load->library('upload', $config);

if(!$this->upload->do_upload()){

    $data['uerrors'] = $this->upload->display_errors();

    if ($data['uerrors']) {
        $this->load->view('partials/header', $data);
        $this->load->view('dashboard/create-post');
        $this->load->view('partials/footer');
    } else {
        $post_image = 'default.jpg';
    }

} else {
    $data = array('upload_data' => $this->upload->data());
    $post_image = $_FILES['userfile']['name'];
}

我认为：

<?php foreach ($uerrors as $uerror): ?>
  <span><?php echo $uerror; ?></span>
<?php endforeach; ?>

<?php if(isset($upload_errors)){
   foreach ($upload_errors as $upload_error) {
    echo $upload_error;
   }
 }?>

---

我的错误在哪里？

此错误告诉您变量不存在或未初始化。看看这个代码

$data['uerrors'] = $this->upload->display_errors();

if ($data['uerrors']) {

---

我认为您可能有一个

$uerrors

变量（未在代码中显示）未初始化。请注意，我不相信

数组

索引

'uerrors'

会在上面的块中给您带来麻烦，因为首先您定义了它，其次，如果您引用了一个不存在的

数组

项，然后，您将收到与问题中引用的错误消息不同的错误消息。

您的问题有点模糊。无论如何，变量

$uerrors

将设置的唯一条件是

create（）

方法将执行的时间，我相信该方法将在POST请求时执行。此外，您没有提到这是视图的哪一部分：

<?php foreach ($uerrors as $uerror): ?>
  <span><?php echo $uerror; ?> </span>
<?php endforeach; ?>

---

您的上传代码看起来不错，但您需要更新以下更改

将数据传递到

'dashboard/create post'

视图，就像传递到

'partials/header'

视图一样。您的

'dashboard/create post'

视图未收到任何上载错误消息，因此它表示

'Undefined variable:uerrors'

。所以，你的上传代码应该是这样的-

正如前面所说，“display_errors（）”返回字符串，而不是数组，您不必遍历错误。只需在您的

“仪表板/创建帖子”

视图中回显即可

为方便起见，请使用不同的方法执行上载任务，以便您也可以在更新方法中重复使用此方法。举例来说-

private function uploadFile(){
    if ($_FILES['userfile']['name'] === '') {
        return array(
            'status' => TRUE,
            'message' => 'No file selected.',
            'file_name' => 'default.jpg'
        );
    }

    // Upload image
    $config['upload_path'] = './assets/img/posts';
    $config['allowed_types'] = 'jpg|jpeg|png';
    $config['max_size'] = '2048';

    $this->load->library('upload', $config);

    if(!$this->upload->do_upload('userfile')){
        return array(
            'status' => FALSE,
            'message' => $this->upload->display_errors('<p class="text-danger ">', '</p>'),
            'file_name' => ''
        );
    }else{
        return array(
            'status' => TRUE,
            'message' => 'File uploaded successfully',
            'file_name' => $this->upload->data('file_name')
        );
    }
}

---

我认为所有这些都应该工作。

您需要将$data['uerrors']初始化为null，因为您正在前端使用它

$data['uerrors'] = '';

或者检查前端上的值是否不为空

前端，您可以通过以下方式执行此操作：

<?php  if (isset($uerrors) && $uerrors != '') {
            foreach ($uerrors as $uerror) {
                echo '<span>' . $uerror . '</span>';
            }
        } ?>

---

你还可以在

上找到有用的帖子我在这里学到了三件事

1） 没有像前面提到的那样将$data传递到正确的视图

2） 视图上应为数组而不是字符串，即数据类型错误

3） 最后，函数do_upload（）需要参数字符串$field。这是丢失的，这就是为什么您只有“无上载选择”错误。如果设置了这个参数，codeigniter会抛出错误的文件类型错误。我这样做是为了测试

依我看

<form action="http://localhost:8000/welcome/create" method="post" enctype="multipart/form-data">
          <input type="file" name="lname" ><br>
          <input type="submit" value="Submit">
        </form>

---

上载错误的文件类型以测试此错误。您可能需要额外的长度来检测实际上载文件的文件类型。

通过以下方式修改

create（）

，我已成功显示上载错误（如果尝试上载，则使用默认图像）：

public function create() {

    // Only logged in users can create posts
    if (!$this->session->userdata('is_logged_in')) {
        redirect('login');
    }

    $data = $this->get_data();
    $data['tagline'] = "Add New Post";

    if ($data['categories']) {
        foreach ($data['categories'] as &$category) {
            $category->posts_count = $this->Posts_model->count_posts_in_category($category->id);
        }
    }

    $this->form_validation->set_rules('title', 'Title', 'required');
    $this->form_validation->set_rules('desc', 'Short description', 'required');
    $this->form_validation->set_rules('body', 'Body', 'required');
    $this->form_validation->set_error_delimiters('<p class="error-message">', '</p>');

    if($this->form_validation->run() === FALSE){
        $this->load->view('partials/header', $data);
        $this->load->view('dashboard/create-post');
        $this->load->view('partials/footer');
    } else {
        // Create slug (from title)
        $slug = url_title(convert_accented_characters($this->input->post('title')), 'dash', TRUE);
        $slugcount = $this->Posts_model->slug_count($slug, null);
        if ($slugcount > 0) {
            $slug = $slug."-".$slugcount;
        }

        // Upload image
        $config['upload_path'] = './assets/img/posts';
        $config['allowed_types'] = 'jpg|jpeg|png';
        $config['max_size'] = '2048';

        $this->load->library('upload', $config);

        if(!$this->upload->do_upload()){

            $errors = array('error' => $this->upload->display_errors());

            // Display upload validation errors 
            // only if a file is uploaded and there are errors
            if (empty($_FILES['userfile']['name'])) {
                $errors = [];
            }

            if (empty($errors)) {
                $post_image = 'default.jpg';
            } else {
                $data['upload_errors'] = $errors;
            }

        } else {
            $data = array('upload_data' => $this->upload->data());
            $post_image = $_FILES['userfile']['name'];
        }

        if (empty($errors)) {
            $this->Posts_model->create_post($post_image, $slug);
            $this->session->set_flashdata('post_created', 'Your post has been created');
            redirect('/');
        } else {
            $this->load->view('partials/header', $data);
            $this->load->view('dashboard/create-post');
            $this->load->view('partials/footer');
        }
    }
}

---

我知道，但我确实将它传递给了

$data

，那么为什么会出现错误？我发布了整个

create（）

方法。@RazvanZamfir它在哪一行崩溃？是不是

if（$data['uerrors'））{

请查看整个控制器，也许这会澄清问题。感谢您的帮助。：）此外，我还检查了视图，没有找到任何foreach循环，以便验证。是正确的文件还是另一个文件？我没有将该部分推送到GitHub，它会引发错误。：）我需要的是一种方法，告诉用户她/他试图加载错误的文件类型（例如PDF），并非没有上载文件。如果没有上载文件，则存在默认图像（请参见

$config['allowed_types']='jpg|jpeg|png'；

）.CodeIgniter不提供任何自定义上载错误消息的选项。相反，您可以执行以下操作-1.告诉用户在创建帖子页面中支持上载哪些文件类型。2.在文件输入中使用

accept

属性。在选择文件时，它将仅显示接受的文件类型。有关详细信息，请检查

W3Schools

属性用法。我已经更新了

uploadFile（）

方法。请用更新的方法替换代码。我自己提供了一个答案，它对

create（）

方法非常有效。但是

update（）给我带来了很大的困难

。请看一看。谢谢！：）这对我来说很有用。检查变量是否为null是解决方案。

$data['uerrors'] = '';

<?php  if (isset($uerrors) && $uerrors != '') {
            foreach ($uerrors as $uerror) {
                echo '<span>' . $uerror . '</span>';
            }
        } ?>

 $data = array();
        // Upload image
        $config['upload_path'] = './assets/img/posts';
        $config['allowed_types'] = 'jpg|jpeg|png';
        $config['max_size'] = '2048';

        $this->load->library('upload', $config);

        /*You need to initialize  $data['uerrors'] as null because you are using it on front end*/
        $data['uerrors'] = '';
        if (!$this->upload->do_upload('FilePath')) {
            $data['uerrors'] = $this->upload->display_errors();
            $this->load->view('partials/header', $data);
            $this->load->view('dashboard/create-post');
            $this->load->view('partials/footer');
        } else {
            if (isset($_POST{'your_file'})) {
                /*'check your images here that you are receiving from front end'*/
            } else {
                /*If there is no image, then default image is*/
                $post_image = 'default.jpg';
            }
            $data = array('upload_data' => $this->upload->data());
            $post_image = $_FILES['userfile']['name'];
        }

<form action="http://localhost:8000/welcome/create" method="post" enctype="multipart/form-data">
          <input type="file" name="lname" ><br>
          <input type="submit" value="Submit">
        </form>

if(!$this->upload->do_upload("lname")){

public function create() {

    // Only logged in users can create posts
    if (!$this->session->userdata('is_logged_in')) {
        redirect('login');
    }

    $data = $this->get_data();
    $data['tagline'] = "Add New Post";

    if ($data['categories']) {
        foreach ($data['categories'] as &$category) {
            $category->posts_count = $this->Posts_model->count_posts_in_category($category->id);
        }
    }

    $this->form_validation->set_rules('title', 'Title', 'required');
    $this->form_validation->set_rules('desc', 'Short description', 'required');
    $this->form_validation->set_rules('body', 'Body', 'required');
    $this->form_validation->set_error_delimiters('<p class="error-message">', '</p>');

    if($this->form_validation->run() === FALSE){
        $this->load->view('partials/header', $data);
        $this->load->view('dashboard/create-post');
        $this->load->view('partials/footer');
    } else {
        // Create slug (from title)
        $slug = url_title(convert_accented_characters($this->input->post('title')), 'dash', TRUE);
        $slugcount = $this->Posts_model->slug_count($slug, null);
        if ($slugcount > 0) {
            $slug = $slug."-".$slugcount;
        }

        // Upload image
        $config['upload_path'] = './assets/img/posts';
        $config['allowed_types'] = 'jpg|jpeg|png';
        $config['max_size'] = '2048';

        $this->load->library('upload', $config);

        if(!$this->upload->do_upload()){

            $errors = array('error' => $this->upload->display_errors());

            // Display upload validation errors 
            // only if a file is uploaded and there are errors
            if (empty($_FILES['userfile']['name'])) {
                $errors = [];
            }

            if (empty($errors)) {
                $post_image = 'default.jpg';
            } else {
                $data['upload_errors'] = $errors;
            }

        } else {
            $data = array('upload_data' => $this->upload->data());
            $post_image = $_FILES['userfile']['name'];
        }

        if (empty($errors)) {
            $this->Posts_model->create_post($post_image, $slug);
            $this->session->set_flashdata('post_created', 'Your post has been created');
            redirect('/');
        } else {
            $this->load->view('partials/header', $data);
            $this->load->view('dashboard/create-post');
            $this->load->view('partials/footer');
        }
    }
}

<?php if(isset($upload_errors)){
   foreach ($upload_errors as $upload_error) {
    echo $upload_error;
   }
 }?>