是否可以在 yii2 中从 ActiveRecord 继承的模型中上传文件？

Question

我用 Gii 从数据库 table 中生成了一个模型 yii2.this 模型继承自 ActiveRecord 。然后我从这个 model.now 创建了一个表单我想用这个表单上传一个文件。是否可以上传具有相同模型（继承自 ActiveRecord）的文件？

如果是，怎么办？如果没有，我该怎么办？

Answer 1

是的，这是可能的，但使用单独的表格是更好的做法。它在文章 Uploading files

的官方文档中有详细描述

创建单独的表单：

namespace app\models;

use yii\base\Model;
use yii\web\UploadedFile;

class UploadForm extends Model
{
    /**
     * @var UploadedFile
     */
    public $imageFile;

    public function rules()
    {
        return [
            [['imageFile'], 'file', 'skipOnEmpty' => false, 'extensions' => 'png, jpg'],
        ];
    }

    public function upload()
    {
        if ($this->validate()) {
            $this->imageFile->saveAs('uploads/' . $this->imageFile->baseName . '.' . $this->imageFile->extension);
            return true;
        } else {
            return false;
        }
    }
}

渲染文件输入：

<?php $form = ActiveForm::begin(['options' => ['enctype' => 'multipart/form-data']]) ?>

    <?= $form->field($model, 'imageFile')->fileInput() ?>

    <button>Submit</button>

<?php ActiveForm::end() ?>

自定义控制器以处理文件上传：

namespace app\controllers;

use Yii;
use yii\web\Controller;
use app\models\UploadForm;
use yii\web\UploadedFile;

class SiteController extends Controller
{
    public function actionUpload()
    {
        $model = new UploadForm();

        if (Yii::$app->request->isPost) {
            $model->imageFile = UploadedFile::getInstance($model, 'imageFile');
            if ($model->upload()) {
                // file is uploaded successfully
                return;
            }
        }

        return $this->render('upload', ['model' => $model]);
    }
}

本文还介绍了上传多个文件。

另见 this related question。

如果要与ActiveRecord一起使用，并将文件路径保存为模型属性，可以在表单的upload()方法中添加模型创建和保存。使用表单的另一个很好的例子是来自 Advanced Template 的 SignupForm：

<?php

namespace frontend\models;
use yii\base\Model;
use common\models\User;

/**
 * Signup form
 */
class SignupForm extends Model
{
    public $username;
    public $email;
    public $password;


    /**
     * @inheritdoc
     */
    public function rules()
    {
        return [
            ['username', 'trim'],
            ['username', 'required'],
            ['username', 'unique', 'targetClass' => '\common\models\User', 'message' => 'This username has already been taken.'],
            ['username', 'string', 'min' => 2, 'max' => 255],
            ['email', 'trim'],
            ['email', 'required'],
            ['email', 'email'],
            ['email', 'string', 'max' => 255],
            ['email', 'unique', 'targetClass' => '\common\models\User', 'message' => 'This email address has already been taken.'],
            ['password', 'required'],
            ['password', 'string', 'min' => 6],
        ];
    }

    /**
     * Signs user up.
     *
     * @return User|null the saved model or null if saving fails
     */
    public function signup()
    {
        if (!$this->validate()) {
            return null;
        }

        $user = new User();
        $user->username = $this->username;
        $user->email = $this->email;
        $user->setPassword($this->password);
        $user->generateAuthKey();

        return $user->save() ? $user : null;
    }
}

如您所见，模型的验证和创建被隔离成单独的形式，这是更好的做法，而不是直接在模型中处理（尤其是文件上传）。但是为了简单的目的，只使用模型也是可以接受的。

是否可以在 yii2 中从 ActiveRecord 继承的模型中上传文件？

is it possible to upload a file in a model that inherits from ActiveRecord in yii2?

file-upload

yii2

yii2-model