array(
 'selectableRows' => 2,
 'footer' => '<button type="button" onclick="GetCheckbox();" style="width:76px">批量删除</button>',
 'class' => 'CCheckBoxColumn',
 'headerHtmlOptions' => array('width'=>'33px'),
 'checkBoxHtmlOptions' => array('name' => 'selectdel[]'),
),

<script type="text/javascript">
/*<![CDATA[*/
var GetCheckbox = function (){
 var data=new Array();
 $("input:checkbox[name='selectdel[]']").each(function (){
  if($(this).attr("checked")==true){
    data.push($(this).val());
  }
 });
 if(data.length > 0){
  $.post('<?php echo CHtml::normalizeUrl(array('/admin/words/delall/'));?>',{'selectdel[]':data}, function (data) {
   var ret = $.parseJSON(data);
   if (ret != null && ret.success != null && ret.success) {
    $.fn.yiiGridView.update('yw1');
   }
  });
 }else{
  alert("请选择要删除的关键字!");
 }
}
/*]]>*/
</script>

public function actionDelall()
{
 if (Yii::app()->request->isPostRequest)
 {
  $criteria= new CDbCriteria;
  $criteria->addInCondition('id', $_POST['selectdel']);
  Words::model()->deleteAll($criteria);//Words换成你的模型
  if(isset(Yii::app()->request->isAjaxRequest)) {
   echo CJSON::encode(array('success' => true));
  } else {
   $this->redirect(isset($_POST['returnUrl']) ? $_POST['returnUrl'] : array('index'));
  }
 }
 else
  throw new CHttpException(400,'Invalid request. Please do not repeat this request again.');
}