如何避免"You did not select a file to upload"？

Question

我有一个带有一些输入的表单和一个可选的文件上传按钮。现在，每当我在不上传图像的情况下提交表单时，就会出现错误"您没有选择要上传的文件"。我想避免此错误，因为我可能并不总是需要上传图像。无论如何有什么可以做的吗？提前致谢。我用于添加文件的控制器如下：

public function add_admin()
{
    $this->data['main_content'] = 'admin/admin_config/index';
    $this->data['sub_content'] = 'admin/admin_config/admin_form';
    $this->load->view(BACKEND, $this->data);
}
public function store_admin()
{
    $post = $this->input->post();
    unset($post['designation'], $post['password'], $post['re_pass']);
    $post['password'] = sha1($this->input->post('password'));
    $post['designation'] = implode(', ', $this->input->post('designation'));
    $c_pass = sha1($this->input->post('re_pass'));
    $image_name = $_FILES['admin_image'];
    $post['filename'] = $image_name['name'];
    $config = [
        'upload_path' => './upload/admin/',
        'allowed_types' => 'jpg|jpeg|png',
    ];
    $this->load->library('upload', $config);
    if ($post) {
        if ($post['password'] == $c_pass && $this->upload->do_upload('admin_image')) {
            $this->adminconfig_model->insert($post);
            set_flash('msg', 'Admin added Successfully!!');
            redirect('admin/adminConfig');
        }else{
            $this->data['error_image'] = $this->upload->display_errors();
            $this->add_admin();
        }
    } else {
        set_flash('dmsg', 'Password do not match!!');
        $this->add_admin();
    }
}

Answer 1

基本上，您需要避免通过检查$_FILES数组是否填充不存在的图像。如果没有上传图像，上传库将始终丢弃该错误。

您也有一些奇怪的逻辑if ($post)始终将其评估为true，因此我们真的不需要它。此外，似乎您的"错误密码"消息在错误的位置。

以下代码将有助于解决这些错误并稍微清理您的代码：

public function store_admin() {
    // post stuff
    $data = array(
        'designation' => implode(', ', $this->input->post('designation')),
        'password' => sha1($this->input->post('password')),
        'filename' => ''
    );
    $c_pass = sha1($this->input->post('re_pass'));
    // first check if passwords match
    if ($data['password'] !== $c_pass) {
        set_flash('dmsg', 'Passwords do not match!');
        $this->add_admin();
    } else {
        $upload = true; // general flag, will be overriden with errors should they occur
        // check if image is uploaded
        if (!empty($_FILES['admin_image']['tmp_name'])) {
            $config = [
                'upload_path' => './upload/admin/',
                'allowed_types' => 'jpg|jpeg|png',
            ];
            $this->load->library('upload', $config);
            if (!$this->upload->do_upload('admin_image')) {
                $upload = $this->upload->display_errors();
            } else {
                // add filename from upload function
                // should do it this way because if overwrite is false
                // upload library will append _1 to the image if it already exists
                $post['filename'] = $this->upload->data('file_name');
            }
        }
        if ($upload !== true) {
            $this->data['error_image'] = $upload;
            $this->add_admin();
        } else {
            $this->adminconfig_model->insert($data);
            set_flash('msg', 'Admin added successfully!');
            redirect('admin/adminConfig');
        }
    }
}