Web Forms :: Unable To Maintain Viewstate Of Dynamically Added User Controls
Apr 24, 2010
I have ONE <asp:Button ID="btnAddUC" runat="server" ......./> and ONE <asp:Table ID="tblUC" runat="server"...> on my page. User clicks on btnAddUC, user control is added to the page [user can add 'n' user controls to the page]. here I have no problem, adding user controls to the page on user clicks.
My user control has ONE <asp:DropDownList ID="ddlItems" runat="server" ......./> and ONE <asp:CheckBoxList ID="chkItems" runat="server"..../>. I am exposing "ddlItems" by public method, "chkItems" is not exposed. "chkItems" is binded on SelectedIndexChanged event of "ddlItems".
Execution scenario:
User adds user control to the page, select item from the "ddlItems" ( Note: "ddlItems" is exposed by public property ) , "chkItems" is populated ( using ddlItems.SelectedItem.Value ) . User checks some checkboxes in "chkItems" and then decide to add one more user control. When the second user control is added to the page, checkboxes in the first usercontrol lose their state and apeears unchecked (NOTE: user checked some checkboxes and then added another user control).
I want to put checked beckboxes index in session ( Before another control is added, which event I should use, because at LOAD event there is nothing).
I was able to restict SelectedIndexChanged event to only that user control whcih generated it (checking _EVENTTARGET)
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[Code]....
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[code]....
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[Code]....
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[Code]....
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[URL]
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[Code]....
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Update:
This is a piece of my user control:
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{
private int PKId
{
get { return ViewState["pkId"] as int; }
set { ViewState["pkId"] = value; }
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{
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}
...
}
I'm following this article to load controls dynamically: http://msdn.microsoft.com/en-us/magazine/cc748662.aspx#id0070065.
Second Update:
I also set the same control ID when I load the user control at first time and on each reaload.
Maybe I can use another method to store these values like input hidden fields or Cache. I've choosen ViewState because I don't want to overload server with Session values for each user.
Third update:
I load the controls with this code:
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}
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[code]....
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[Code]....
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here is my code
[Code]....
[Code]....
[Code]....
[Code]....
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[code]...
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