在ASP.NET的Ajax更新面板中使用AsyncPostBackTrigger时未启用ImageButton

Question

i am using asp.net with c#. i have two image buttons : open and delete. By default they are disabled ie imgOpen.Enabled = false; imgDelete.Enabled = false; imgOpen.Enabled = false; imgDelete.Enabled = false; . I have a GridView which shows search results from table. GridView contains a radio button which when selected, should enable Open and delete image button. if I won't use ajax update panel, then every time i select a radio button my page reloads and it's quite disturbing and not friendly.

<asp:TemplateField>
     <ItemTemplate>
          <asp:UpdatePanel ID="updateRadioButton" runat="server">
              <ContentTemplate>
                  <asp:RadioButton ID="rdoBtnFileOption" runat="server" OnCheckedChanged="rdoBtnFileOption_CheckedChanged"  AutoPostBack="true" />
               </ContentTemplate>
               <Triggers>
               <asp:AsyncPostBackTrigger ControlID="rdoBtnFileOption" EventName="CheckedChanged" />
               </Triggers>
          </asp:UpdatePanel>
     </ItemTemplate>
</asp:TemplateField>



protected void rdoBtnFileOption_CheckedChanged(object sender, EventArgs e)
    {
        imgOpen.Enabled = true;
        imgDelete.Enabled = true;

        RadioButton curretnRdo = sender as RadioButton;
        GridViewRow currentRow = (GridViewRow)curretnRdo.NamingContainer;
        int index = currentRow.RowIndex;
        try
        {
            foreach (GridViewRow grv in grdSearchResults.Rows)
            {
                if (grv.RowType == DataControlRowType.DataRow && grv.RowIndex != index)
                {
                    RadioButton rdo = new RadioButton();
                    rdo = (RadioButton)(grv.FindControl("rdoBtnFileOption"));
                    rdo.Checked = false;
                }
            }
        }
        catch (Exception ex)
        {
            form.MessageBox.Show(ex.Message, "Error", form.MessageBoxButtons.OK, form.MessageBoxIcon.Error);
        }

    }

These two line are not working for me.

imgOpen.Enabled = true;
imgDelete.Enabled = true;

Please Suggest any approach. I hope i am quite clear.

Answer 1

Try the following

Wrap your imgDelete with another UpdatePanel and set UpdateMode=Conditional and set Trigger

<asp:UpdatePanel ID="updateRadioButton" UpdateMode="Conditional" runat="server">
   <ContentTemplate>
   <asp:Image ID="imgOpen" runat="server"/>
   <asp:Image ID="imgDelete" runat="server"/>
   </ContentTemplate>
   <Triggers>
   <asp:AsyncPostBackTrigger ControlID="rdoBtnFileOption" 
      EventName="CheckedChanged" />
   </Triggers>
</asp:UpdatePanel>

or set UpdateMode="Always" and No Triggers

Answer 2

For using AsyncPostBack, the contents should be in Update panel also.

you can use another Asp:UpdatePanel with UpdateMode="Always" having your images in it.

<asp:UpdatePanel ID="UP1" runat="server" UpdateMode="Always">
            <ContentTemplate>
                <asp:ImageButton ID="imgOpen" runat="server" ImageUrl="" Visible="false" AlternateText="this is Open Image" />
                <asp:ImageButton ID="imgDelete" runat="server" ImageUrl="" Visible="false" AlternateText="this is Delete Image" />
            </ContentTemplate>
</asp:UpdatePanel>

May this Help You.