yii Trying to get property of non-object错误

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Title:yii Trying to get property of non-object错误
Author:insun
Blog:http://yxmhero1989.blog.163.com
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yiic 去执行时候因为调用另外一个model 所以可能会出现Trying to get property of non-object

所以在要在调用model之前判断这个model是否存在

 

 这样的代码，就会出现上面的错误。
    public function getCityName($id)
    {
        $model = City::model()->findByPk($id);
            return $model->name;
    }

一定要做个判断，正确的如下：

    public function getCityName($id)
    {
        $model = City::model()->findByPk($id);
        
        if($model){
            return $model->name;
        }
        else{
            return null;
        }
    }

 

譬如：

/**

 * Returns the data model based on the primary key given in the GET variable.

 * If the data model is not found, an HTTP exception will be raised.

 * @param integer the ID of the model to be loaded

 */

public function loadModel($id)

{

$model=Member::model()->findByPk($id);

if($model===null)

throw new CHttpException(404,'抱歉，你请求的页面不存在.');

return $model;

}