Question

I have a dialog popup with a textearea, two listboxes and one button. By selecting a value in the first listbox and pressing the button “>” the selected value is passed to the second listbox. This is done with asp.net ajax.

<td>
    <div align="center">
           <textarea style="height:50px; overflow:hidden;";rows="20"
              cols="40"
              id="editor1" 
              class="tinymce">
           </textarea>
    </div>
</td>

I put the 2 listboxes and the button between asp.net uploadpanel. Like this:

<td>
                        <asp:UpdatePanel runat="server" id="updatePanel1">
                            <ContentTemplate>
                            <table width="100%" align="left">
                                            <tr>
                                                <td colspan="5">
                                                    <hr align="left" style="width:95%" />
                                                </td>
                                            </tr>
                                            <tr>
                                                <td valign="top">
                                                    <cc1:SWCListBox
                                                        ID="SWCListBox1" 
                                                            runat="server" 
                                                            Width="100"
                                                            SelectionMode="Single" 
                                                            CssClass="VW1">

                                                        </cc1:SWCListBox>
                                                </td>
                                                <td 
                                                    valign="top" 
                                                    width="50" 
                                                    align="center">
                                                    <cc1:SWCButton
                                                        Text=" > " 
                                                        ID="SWCBtnAddValue" 
                                                        CssClass="VW1 VWButton" 
                                                        runat="server" 
                                                        ToolTip="Add to list"
                                                        OnClick="AddValue_Click"
                                                        CausesValidation="false"
                                                        />

                                                <td valign="top">
                                                            <cc1:SWCListBox
                                                                id="SWCListBox2"
                                                                CssClass="VW1" 
                                                                runat="server" 
                                                                Width="100" 
                                                                SelectionMode="Single"
                                                        />

                                                </td>
                                                </tr>
                                        </table>
                                      </ContentTemplate>
                                    </asp:UpdatePanel>

The probles is that when I type something in the textarea and make an async postback the text typed fades.

How can I keep the textarea value within async postbacks?
thank you.

Answer 1

This problem is because you use UpdatePanel, and the textarea is not an asp.net control. You have two solutions.

1) Make it asp.net control by placing the run=”server” (or)
2) Place the post back value manually as:

<div align="center">
       <textarea style="height:50px; overflow:hidden;";rows="20"
          cols="40"
          id="editor1" 
          name="editor_1"
          class="tinymce">
       <asp:Literal runat="server" id="txtEditor1" />
       </textarea>
</div>

and on code behind

txtEditor1.Text = Server.HtmlEncode(Request.Form["editor_1"].ToString());

(because you use UpdatePanel its important to use Literal to add this value and not use <%=%>, or else its throw an error.