刚才写错了以下是报错信息
************** 异常文本 **************
System.NullReferenceException: 未将对象引用设置到对象的实例。
at EM.EquipmentManage.frm.frmEquipmentType.frmLargetype_Closed(Object sender, EventArgs e)
at System.Windows.Forms.Form.OnClosed(EventArgs e)
at System.Windows.Forms.Form.CheckCloseDialog()
string ret=(frmLargetype.Tag != null ? frmLargetype.Tag.ToString() : "" );