yii2用表单上传文件经常用到的，该怎样上传呢？

1、单个文件上传

首先建立一个模型models/UploadForm.php,内容如下

namespace app\models;use yii\base\Model;use yii\web\UploadedFile;/** * UploadForm is the model behind the upload form. */class UploadForm extends Model{ /** * @var UploadedFile file attribute */ public $file; /** * @return array the validation rules. */ public function rules() { return [ [['file'], 'file'], ]; }}

再建立一个视图文件，内容如下

<?phpuse yii\widgets\ActiveForm;?><?php $form = ActiveForm::begin(['options' => ['enctype' => 'multipart/form-data']]) ?><?= $form->field($model, 'file')->fileInput() ?><button>Submit</button><?php ActiveForm::end() ?>

最后建立控制器文件，内容如下

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) { $model->file = UploadedFile::getInstance($model, 'file'); if ($model->file && $model->validate()) { $model->file->saveAs('uploads/' . $model->file->baseName . '.' . $model->file->extension); } } return $this->render('upload', ['model' => $model]); }}

注意这里我们没有用model->load(...)，而是用了UploadedFile::getInstance(...)。区别是后者不会执行$model->validate()，所以需要手动的去执行$model->validate()来检验数据的合法性。如果检验通过了，上传的文件保存在uploads文件夹下，即web目录下的uploads里。

一些可选的配置选项

上传文件不能为空

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

上传类型，不仅可以根据扩展名检验，还可以根据文件的内容进行检验

public function rules(){ return [ [['file'], 'file', 'extensions' => 'jpg, png', 'mimeTypes' => 'image/jpeg, image/png',], ];}

2、多文件上传

如果你想一次上传多个文件，只需调节几个参数就可以达到目的

Model：

class UploadForm extends Model{ /** * @var UploadedFile|Null file attribute */ public $file; /** * @return array the validation rules. */ public function rules() { return [ [['file'], 'file', 'maxFiles' => 10], // <--- here! ]; }}

View：

<?phpuse yii\widgets\ActiveForm;$form = ActiveForm::begin(['options' => ['enctype' => 'multipart/form-data']]);?><?= $form->field($model, 'file[]')->fileInput(['multiple' => true]) ?> <button>Submit</button><?php ActiveForm::end(); ?>

与单文件上传不同的是下面这句

$form->field($model, 'file[]')->fileInput(['multiple' => true])

Controller:

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) { $model->file = UploadedFile::getInstances($model, 'file'); if ($model->file && $model->validate()) { foreach ($model->file as $file) { $file->saveAs('uploads/' . $file->baseName . '.' . $file->extension); } } } return $this->render('upload', ['model' => $model]); }}

这样就可以实现多文件上传了。

参考https://github.com/yiisoft/yii2/blob/master/docs/guide/input-file-upload.md

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。