1、首先在config\main.php中添加对PHPExcel的引用，我的方式是这样：

// autoloading model and component classes
'import'=>array(
    /*'application.modules.srbac.controllers.SBaseController',*/
    'application.models.*',
    'application.components.*',
    'application.extensions.phpexcel.*',
),

另外也有人用components 这个配置，但是我的有问题，所以就用上面的方法。

2、按照下面的代码修改PHPExcel代码目录里的Autoloader.php文件：

public static function Register() {
    /*if (function_exists('__autoload')) {
      //  Register any existing autoloader function with SPL, so we don't get any clashes
      spl_autoload_register('__autoload');
    }
    //  Register ourselves with SPL
    return spl_autoload_register(array('PHPExcel_Autoloader', 'Load'));*/
    $functions = spl_autoload_functions();
      foreach ( $functions as $function)
        spl_autoload_unregister($function);
      $functions = array_merge(array(array('PHPExcel_Autoloader','Load')),$functions);
      foreach ( $functions as $function)
        $x = spl_autoload_register($function);
      return $x;
}  //  function Register()

上面的函数中，注释掉的是原有的代码。

3、下面的代码是输出Excel，以及一些常用的属性设置，在你的controller中：

/*
导出为Excel
*/
public function actionExport()
{
    $objectPHPExcel = new PHPExcel();
    $objectPHPExcel->setActiveSheetIndex(0);
    $page_size = 52;
    //数据的取出
    $model = Yii::app()->session['printdata'];
    $dataProvider = $model->search();
    $dataProvider->setPagination(false);
    $data = $dataProvider->getData();
    $count = $dataProvider->getTotalItemCount();
    //总页数的算出
    $page_count = (int)($count/$page_size) +1;
    $current_page = 0;
    $n = 0;
    foreach ( $data as $product )
    {
      if ( $n % $page_size === 0 )
      {
        $current_page = $current_page +1;
        //报表头的输出
        $objectPHPExcel->getActiveSheet()->mergeCells('B1:G1');
        $objectPHPExcel->getActiveSheet()->setCellValue('B1','产品信息表');
        $objectPHPExcel->setActiveSheetIndex(0)->setCellValue('B2','产品信息表');
        $objectPHPExcel->setActiveSheetIndex(0)->setCellValue('B2','产品信息表');
        $objectPHPExcel->setActiveSheetIndex(0)->getStyle('B1')->getFont()->setSize(24);
        $objectPHPExcel->setActiveSheetIndex(0)->getStyle('B1')
          ->getAlignment()->setHorizontal(PHPExcel_Style_Alignment::HORIZONTAL_CENTER);
        $objectPHPExcel->setActiveSheetIndex(0)->setCellValue('B2','日期：'.date("Y年m月j日"));
        $objectPHPExcel->setActiveSheetIndex(0)->setCellValue('G2','第'.$current_page.'/'.$page_count.'页');
        $objectPHPExcel->setActiveSheetIndex(0)->getStyle('G2')
          ->getAlignment()->setHorizontal(PHPExcel_Style_Alignment::HORIZONTAL_RIGHT);
        //表格头的输出
        $objectPHPExcel->getActiveSheet()->getColumnDimension('A')->setWidth(5);
        $objectPHPExcel->setActiveSheetIndex(0)->setCellValue('B3','编号');
        $objectPHPExcel->getActiveSheet()->getColumnDimension('B')->setWidth(6.5);
        $objectPHPExcel->setActiveSheetIndex(0)->setCellValue('C3','名称');
        $objectPHPExcel->getActiveSheet()->getColumnDimension('C')->setWidth(17);
        $objectPHPExcel->setActiveSheetIndex(0)->setCellValue('D3','生产厂家');
        $objectPHPExcel->getActiveSheet()->getColumnDimension('D')->setWidth(22);
        $objectPHPExcel->setActiveSheetIndex(0)->setCellValue('E3','单位');
        $objectPHPExcel->getActiveSheet()->getColumnDimension('E')->setWidth(15);
        $objectPHPExcel->setActiveSheetIndex(0)->setCellValue('F3','单价');
        $objectPHPExcel->getActiveSheet()->getColumnDimension('F')->setWidth(15);
        $objectPHPExcel->setActiveSheetIndex(0)->setCellValue('G3','在库数');
        $objectPHPExcel->getActiveSheet()->getColumnDimension('G')->setWidth(15);
        //设置居中
        $objectPHPExcel->getActiveSheet()->getStyle('B3:G3')
          ->getAlignment()->setHorizontal(PHPExcel_Style_Alignment::HORIZONTAL_CENTER);
        //设置边框
        $objectPHPExcel->getActiveSheet()->getStyle('B3:G3' )
          ->getBorders()->getTop()->setBorderStyle(PHPExcel_Style_Border::BORDER_THIN);
        $objectPHPExcel->getActiveSheet()->getStyle('B3:G3' )
          ->getBorders()->getLeft()->setBorderStyle(PHPExcel_Style_Border::BORDER_THIN);
        $objectPHPExcel->getActiveSheet()->getStyle('B3:G3' )
          ->getBorders()->getRight()->setBorderStyle(PHPExcel_Style_Border::BORDER_THIN);
        $objectPHPExcel->getActiveSheet()->getStyle('B3:G3' )
          ->getBorders()->getBottom()->setBorderStyle(PHPExcel_Style_Border::BORDER_THIN);
        $objectPHPExcel->getActiveSheet()->getStyle('B3:G3' )
          ->getBorders()->getVertical()->setBorderStyle(PHPExcel_Style_Border::BORDER_THIN);
        //设置颜色
        $objectPHPExcel->getActiveSheet()->getStyle('B3:G3')->getFill()
          ->setFillType(PHPExcel_Style_Fill::FILL_SOLID)->getStartColor()->setARGB('FF66CCCC');
      }
      //明细的输出
      $objectPHPExcel->getActiveSheet()->setCellValue('B'.($n+4) ,$product->id);
      $objectPHPExcel->getActiveSheet()->setCellValue('C'.($n+4) ,$product->product_name);
      $objectPHPExcel->getActiveSheet()->setCellValue('D'.($n+4) ,$product->product_agent->name);
      $objectPHPExcel->getActiveSheet()->setCellValue('E'.($n+4) ,$product->unit);
      $objectPHPExcel->getActiveSheet()->setCellValue('F'.($n+4) ,$product->unit_price);
      $objectPHPExcel->getActiveSheet()->setCellValue('G'.($n+4) ,$product->library_count);
      //设置边框
      $currentRowNum = $n+4;
      $objectPHPExcel->getActiveSheet()->getStyle('B'.($n+4).':G'.$currentRowNum )
          ->getBorders()->getTop()->setBorderStyle(PHPExcel_Style_Border::BORDER_THIN);
      $objectPHPExcel->getActiveSheet()->getStyle('B'.($n+4).':G'.$currentRowNum )
          ->getBorders()->getLeft()->setBorderStyle(PHPExcel_Style_Border::BORDER_THIN);
      $objectPHPExcel->getActiveSheet()->getStyle('B'.($n+4).':G'.$currentRowNum )
          ->getBorders()->getRight()->setBorderStyle(PHPExcel_Style_Border::BORDER_THIN);
      $objectPHPExcel->getActiveSheet()->getStyle('B'.($n+4).':G'.$currentRowNum )
          ->getBorders()->getBottom()->setBorderStyle(PHPExcel_Style_Border::BORDER_THIN);
      $objectPHPExcel->getActiveSheet()->getStyle('B'.($n+4).':G'.$currentRowNum )
          ->getBorders()->getVertical()->setBorderStyle(PHPExcel_Style_Border::BORDER_THIN);
      $n = $n +1;
    }
    //设置分页显示
    //$objectPHPExcel->getActiveSheet()->setBreak( 'I55' , PHPExcel_Worksheet::BREAK_ROW );
    //$objectPHPExcel->getActiveSheet()->setBreak( 'I10' , PHPExcel_Worksheet::BREAK_COLUMN );
    $objectPHPExcel->getActiveSheet()->getPageSetup()->setHorizontalCentered(true);
    $objectPHPExcel->getActiveSheet()->getPageSetup()->setVerticalCentered(false);
    ob_end_clean();
    ob_start();
    header('Content-Type : application/vnd.ms-excel');
    header('Content-Disposition:attachment;filename="'.'产品信息表-'.date("Y年m月j日").'.xls"');
    $objWriter= PHPExcel_IOFactory::createWriter($objectPHPExcel,'Excel5');
    $objWriter->save('php://output');
}