每个下拉列表抛出“对象引用未设置为对象的实例”，无论它们在哪个页面上

Question

将属性“autopostback”设置为true的每个下拉列表都会在运行时抛出“对象引用未设置为对象的实例”。 调试时不会抛出任何错误。 它们在哪个页面上或者即使它们绑定到数据源似乎也不重要。 自从他们开始这样做以来，我的配置中没有任何内容被更改。

.net错误如下：

    Server Error in '/Nominations' Application.
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Object reference not set to an instance of an object. 
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.NullReferenceException: Object reference not set to an instance of an object.

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: 


[NullReferenceException: Object reference not set to an instance of an object.]
   DevExpress.Web.ASPxMenu.Internal.MenuHorizontalSpacingControl.PrepareSpacingControl(WebControl control, MenuItem item, Boolean isSeparatorSpacing) +119
   DevExpress.Web.ASPxMenu.Internal.MenuHorizontalSpacingControl.PrepareControlHierarchy() +80
   DevExpress.Web.ASPxClasses.Internal.InternalTableCell.Render(HtmlTextWriter writer) +47
   System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +25
   System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +134
   System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +19
   System.Web.UI.WebControls.WebControl.RenderContents(HtmlTextWriter writer) +10
   System.Web.UI.WebControls.WebControl.Render(HtmlTextWriter writer) +32
   DevExpress.Web.ASPxClasses.Internal.InternalTableRow.Render(HtmlTextWriter writer) +58
   System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +25
   System.Web.UI.WebControls.Table.RenderContents(HtmlTextWriter writer) +206
   DevExpress.Web.ASPxClasses.Internal.InternalTable.RenderContents(HtmlTextWriter writer) +81
   System.Web.UI.WebControls.WebControl.Render(HtmlTextWriter writer) +32
   DevExpress.Web.ASPxClasses.Internal.InternalTable.Render(HtmlTextWriter writer) +186
   System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +25
   System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +134
   System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +19
   System.Web.UI.WebControls.WebControl.RenderContents(HtmlTextWriter writer) +10
   DevExpress.Web.ASPxClasses.ASPxWebControlBase.RenderInternal(HtmlTextWriter writer) +73
   DevExpress.Web.ASPxClasses.ASPxWebControlBase.Render(HtmlTextWriter writer) +67
   System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +25
   System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +134
   System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +19
   System.Web.UI.WebControls.TableCell.RenderContents(HtmlTextWriter writer) +57
   System.Web.UI.WebControls.WebControl.Render(HtmlTextWriter writer) +32
   DevExpress.Web.ASPxClasses.Internal.InternalTableCell.Render(HtmlTextWriter writer) +58
   System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +25
   System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +134
   System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +19
   System.Web.UI.WebControls.WebControl.RenderContents(HtmlTextWriter writer) +10
   System.Web.UI.WebControls.WebControl.Render(HtmlTextWriter writer) +32
   DevExpress.Web.ASPxClasses.Internal.InternalTableRow.Render(HtmlTextWriter writer) +58
   System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +25
   System.Web.UI.WebControls.Table.RenderContents(HtmlTextWriter writer) +206
   DevExpress.Web.ASPxClasses.Internal.InternalTable.RenderContents(HtmlTextWriter writer) +81
   System.Web.UI.WebControls.WebControl.Render(HtmlTextWriter writer) +32
   DevExpress.Web.ASPxClasses.Internal.InternalTable.Render(HtmlTextWriter writer) +186
   System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +25
   System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +134
   System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +19
   System.Web.UI.WebControls.WebControl.RenderContents(HtmlTextWriter writer) +10
   DevExpress.Web.ASPxClasses.ASPxWebControlBase.RenderInternal(HtmlTextWriter writer) +73
   DevExpress.Web.ASPxClasses.ASPxWebControlBase.Render(HtmlTextWriter writer) +67
   System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +25
   System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +134
   System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +19
   System.Web.UI.WebControls.WebControl.RenderContents(HtmlTextWriter writer) +10
   DevExpress.Web.ASPxClasses.ASPxWebControlBase.RenderInternal(HtmlTextWriter writer) +73
   DevExpress.Web.ASPxClasses.ASPxWebControlBase.Render(HtmlTextWriter writer) +67
   System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +25
   System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +134
   System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +19
   System.Web.UI.WebControls.WebControl.RenderContents(HtmlTextWriter writer) +10
   DevExpress.Web.ASPxClasses.ASPxWebControlBase.RenderInternal(HtmlTextWriter writer) +73
   DevExpress.Web.ASPxClasses.ASPxWebControl.RenderInternal(HtmlTextWriter writer) +205
   DevExpress.Web.ASPxClasses.ASPxWebControlBase.Render(HtmlTextWriter writer) +67
   System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +25
   System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +134
   System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +19
   System.Web.UI.HtmlControls.HtmlForm.RenderChildren(HtmlTextWriter writer) +163
   System.Web.UI.HtmlControls.HtmlContainerControl.Render(HtmlTextWriter writer) +32
   System.Web.UI.HtmlControls.HtmlForm.Render(HtmlTextWriter output) +51
   System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99
   System.Web.UI.HtmlControls.HtmlForm.RenderControl(HtmlTextWriter writer) +40
   System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +134
   System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +19
   System.Web.UI.Control.Render(HtmlTextWriter writer) +10
   System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +25
   System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +134
   System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +19
   System.Web.UI.Page.Render(HtmlTextWriter writer) +29
   System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +25
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1266




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Version Information: Microsoft .NET Framework Version:2.0.50727.4206; ASP.NET Version:2.0.50727.4209 

有没有人有任何想法？

Answer 1

这是DevExpress菜单控件的一些东西，我猜它是在一个母版页上，这就是为什么它发生在每一页上。 至于为什么，我不认为它与下拉控制有关，只是因为它回发了。

您将需要查看该控件从何处获取数据，以查看该数据是否为null或者可能与DevExpress联系以查看它是否是控件的问题。