GridView中CommandField问题

我用了分页存储过程绑定GridView,绑定很正常,并加上了
<asp:CommandField ShowEditButton="True" />
编辑按钮,但测试的时候一点这个按钮就会出错,下面是出错的提示,我实在看不懂,不知道问题出在哪里.(好像一定要用Gridview自带的DataSource才行)
/**************以下是错误提示**********************/
The GridView 'gv_mstr' fired event RowEditing which wasn't handled.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.Web.HttpException: The GridView 'gv_mstr' fired event RowEditing which wasn't handled.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:


[HttpException (0x80004005): The GridView 'gv_mstr' fired event RowEditing which wasn't handled.]
System.Web.UI.WebControls.GridView.OnRowEditing(GridViewEditEventArgs e) +324
System.Web.UI.WebControls.GridView.HandleEdit(Int32 rowIndex) +60
System.Web.UI.WebControls.GridView.HandleEvent(EventArgs e, Boolean causesValidation, String validationGroup) +705
System.Web.UI.WebControls.GridView.RaisePostBackEvent(String eventArgument) +214
System.Web.UI.WebControls.GridView.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +31
System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +32
System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +244
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +3837