event not firing: DropDownList or else generates error at runtime

[Brian Fulford]

Related to using VB as code behind language.

ASPX page control: when OnSelectedIndexChanged attribute is not added page renders fine but no event fires; when attribute is added to indicate the event sub to go to, an error is generated as follows:

? server.GetLastError

{System.Web.HttpException}

[System.Web.HttpException]: {System.Web.HttpException}

HelpLink: Nothing

InnerException: {System.Web.HttpCompileException}

Message: "External component has thrown an exception."

Source: "System.Web"

Actual ASPX html:

<aspropDownList id="ddlDateRange" runat="server" Width="150px" AutoPostBack="false" OnSelectedIndexChanged="ddlDateRange_SelectedIndexChanged"></aspropDownList>

VB code behind:

Public Class ccsm_filters2

Inherits System.Web.UI.Page

#Region " Web Form Designer Generated Code "

Protected WithEvents UltraWebTab1 As Infragistics.WebUI.UltraWebTab.UltraWebTab

Public ddlDateRange As DropDownList



Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

Private Sub ddlDateRange_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs)

Select Case ddlDateRange.SelectedIndex



I guess I am not sure how the event should be wired so as to fire and I need to change variables and labels based upon what the user picked from the drop down list. Any help would be much appreciated.



Brian

 

[jagadeesh]

Are the labels are in the same page? In that case you need to make the autopostback property true. This will fire the event properly. Try setting this property.

Related to using VB as code behind language.

ASPX page control: when OnSelectedIndexChanged attribute is not added page renders fine but no event fires; when attribute is added to indicate the event sub to go to, an error is generated as follows:

? server.GetLastError

{System.Web.HttpException}

[System.Web.HttpException]: {System.Web.HttpException}

HelpLink: Nothing

InnerException: {System.Web.HttpCompileException}

Message: "External component has thrown an exception."

Source: "System.Web"

Actual ASPX html:

<aspropDownList id="ddlDateRange" runat="server" Width="150px" AutoPostBack="false" OnSelectedIndexChanged="ddlDateRange_SelectedIndexChanged"></aspropDownList>

VB code behind:

Public Class ccsm_filters2

Inherits System.Web.UI.Page

#Region " Web Form Designer Generated Code "

Protected WithEvents UltraWebTab1 As Infragistics.WebUI.UltraWebTab.UltraWebTab

Public ddlDateRange As DropDownList



Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

Private Sub ddlDateRange_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs)

Select Case ddlDateRange.SelectedIndex



I guess I am not sure how the event should be wired so as to fire and I need to change variables and labels based upon what the user picked from the drop down list. Any help would be much appreciated.



Brian

 

[Brian Fulford]

That did not help out the situation, same error as before. As long as I leave out the onSelectedIndexChanged event on the server control tag, the page loads fine but of course there is no event wiring.

Any other suggestions as to the cause or resolution?
Are the labels are in the same page? In that case you need to make the autopostback property true. This will fire the event properly. Try setting this property.

Related to using VB as code behind language.

ASPX page control: when OnSelectedIndexChanged attribute is not added page renders fine but no event fires; when attribute is added to indicate the event sub to go to, an error is generated as follows:

? server.GetLastError

{System.Web.HttpException}

[System.Web.HttpException]: {System.Web.HttpException}

HelpLink: Nothing

InnerException: {System.Web.HttpCompileException}

Message: "External component has thrown an exception."

Source: "System.Web"

Actual ASPX html:

<aspropDownList id="ddlDateRange" runat="server" Width="150px" AutoPostBack="false" OnSelectedIndexChanged="ddlDateRange_SelectedIndexChanged"></aspropDownList>

VB code behind:

Public Class ccsm_filters2

Inherits System.Web.UI.Page

#Region " Web Form Designer Generated Code "

Protected WithEvents UltraWebTab1 As Infragistics.WebUI.UltraWebTab.UltraWebTab

Public ddlDateRange As DropDownList



Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

Private Sub ddlDateRange_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs)

Select Case ddlDateRange.SelectedIndex



I guess I am not sure how the event should be wired so as to fire and I need to change variables and labels based upon what the user picked from the drop down list. Any help would be much appreciated.



Brian