yii2.0图片上传

在根目录下夹uploads文件夹

控制器   UploadController.php

<?php
namespace frontend\controllers;

use Yii;
use frontend\models\UploadForm;
use yii\web\UploadedFile;

class UploadController extends \yii\web\Controller
{

 　　public function actionUpload(){
        //实例化model
        $model = new UploadForm();
        // 判断是否是POST表单提交
        if (Yii::$app->request->isPost) {

            $model->file = UploadedFile::getInstance($model,'file');
//            var_export($model->file);die;
            if($model->file->saveAs(\yii::$app->basePath.'/../uploads/'.$model->file->baseName.'.'. $model->file->extension)){
                 $this->redirect(['site/index']);
            }else{
                echo"上传失败";
            }
        } else {
                    return $this->render('upload', ['model' => $model]);
        }

    }

} 

model层UploadForm.php

<?php
namespace frontend\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']
        ];
    }
}

view里面upload.php

<?php
use yii\widgets\ActiveForm;
use yii\helpers\Html;
?>

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

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

    <button>提交</button>

<?php ActiveForm::end() ?>

<?= Html::img('@web/uploads/1.jpg', ['alt' => 'My logo']) ?>