templates/example.controller.php
public function actionImport()
    {
        $field = [
            'fileImport' => 'File Import',
        ];
        
        $modelImport = DynamicModel::validateData($field, [
            [['fileImport'], 'required'],
            [['fileImport'], 'file', 'extensions'=>'xls,xlsx','maxSize'=>1024*1024],
        ]);

        if (Yii::$app->request->post()) {
            $modelImport->fileImport = \yii\web\UploadedFile::getInstance($modelImport, 'fileImport');
            if ($modelImport->fileImport && $modelImport->validate()) {                                
                $inputFileType = \PHPExcel_IOFactory::identify($modelImport->fileImport->tempName );
                $objReader = \PHPExcel_IOFactory::createReader($inputFileType);
                $objPHPExcel = $objReader->load($modelImport->fileImport->tempName);
                $sheetData = $objPHPExcel->getActiveSheet()->toArray(null,true,true,true);
                $baseRow = 2;
                while(!empty($sheetData[$baseRow]['A'])){
                    $model = new Mahasiswa();
                    $model->nama = (string)$sheetData[$baseRow]['B'];
                    $model->nim = (string)$sheetData[$baseRow]['C'];
                    $model->save(); 
                    //die(print_r($model->errors));
                    $baseRow++;
                }
                Yii::$app->getSession()->setFlash('success', 'Success');
            }
            else{
                Yii::$app->getSession()->setFlash('error', 'Error');
            }
        }
        
        return $this->redirect(['index']);
    }
public function actionImport()
    {
        $field = [
            'fileImport' => 'File Import',
        ];
        
        $modelImport = DynamicModel::validateData($field, [
            [['fileImport'], 'required'],
            [['fileImport'], 'file', 'extensions'=>'xls,xlsx','maxSize'=>1024*1024],
        ]);

        if (Yii::$app->request->post()) {
            $modelImport->fileImport = \yii\web\UploadedFile::getInstance($modelImport, 'fileImport');
            if ($modelImport->fileImport && $modelImport->validate()) {                                
                $inputFileType = \PHPExcel_IOFactory::identify($modelImport->fileImport->tempName );
                $objReader = \PHPExcel_IOFactory::createReader($inputFileType);
                $objPHPExcel = $objReader->load($modelImport->fileImport->tempName);
                $sheetData = $objPHPExcel->getActiveSheet()->toArray(null,true,true,true);
                $baseRow = 2;
                while(!empty($sheetData[$baseRow]['A'])){
                    $model = new Mahasiswa();
                    $model->nama = (string)$sheetData[$baseRow]['B'];
                    $model->nim = (string)$sheetData[$baseRow]['C'];
                    $model->save(); 
                    //die(print_r($model->errors));
                    $baseRow++;
                }
                Yii::$app->getSession()->setFlash('success', 'Success');
            }
            else{
                Yii::$app->getSession()->setFlash('error', 'Error');
            }
        }
        
        return $this->redirect(['index']);
    }
/*
IMPORT WITH PHPEXCEL