Control 'TopHeader_username' of type 'TextBox' must be placed inside a form tag with runat=server.

Server Error in '/' Application.

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Control 'TopHeader_username' of type 'TextBox' must be placed inside a form tag with runat=server.

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: Control 'TopHeader_username' of type 'TextBox' must be placed inside a form tag with runat=server.

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): Control 'TopHeader_username' of type 'TextBox' must be placed inside a form tag with runat=server.] System.Web.UI.Page.VerifyRenderingInServerForm(Control control) +2045183 System.Web.UI.WebControls.TextBox.AddAttributesToRender(HtmlTextWriter writer) +48 System.Web.UI.WebControls.WebControl.RenderBeginTag(HtmlTextWriter writer) +17 System.Web.UI.WebControls.TextBox.Render(HtmlTextWriter writer) +17 System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +25 System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +121 System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +22 System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +130 System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +24 System.Web.UI.Control.Render(HtmlTextWriter writer) +7 System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +25 System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +121 System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +22 System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +130 System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +24 System.Web.UI.Page.Render(HtmlTextWriter writer) +26 System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +25 System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +121 System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +22 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1896

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Version Information: Microsoft .NET Framework Version:2.0.50727.832; ASP.NET Version:2.0.50727.832



问题分析:
造成这样的问题出现是因为:服务器控件没有包括在标有runat=server的Form标记中,
ASP.NET必须把每个服务器控件放入带有Runat=server的Form标记