Using the code from the Ext.net example, I need the value of the text in HtmlEditor1 :

Server Side:
<script runat="server">
    protected void CompleteEdit(object sender, DirectEventArgs e)
    {
         string myMessage = e.ExtraParams["value"];
    }
[/COLOR]</script>
Client Code:
 <ext:Panel ID="Tab3" runat="server" Title="Ajax Update">    <Items>
      <ext:Label
        ID="AjaxLabel"
        runat="server"
        Cls="editable"
        Icon="NoteEdit"
        OverCls="editable-over"
        Text="Ajax Label">
        <Editor>
          <ext:Editor
            ID="AjaxLabelEditor"
            runat="server"
            Shadow="false"
            Alignment="tl-tl?"
            UpdateEl="false">
            <AutoSizeConfig Width="BoundEl" />
            <DirectEvents>
              <Complete OnEvent="CompleteEdit">
                <EventMask
                  ShowMask="true"
                  Target="CustomTarget"
                  CustomTarget="={#{Tab3}.body}" />
                <ExtraParams>
                  <ext:Parameter Name="value" Value="value" Mode="Raw" />
                </ExtraParams>
              </Complete>
            </DirectEvents>
          </ext:Editor>
        </Editor>
      </ext:Label>
    </Items>
  </ext:Panel>


  <ext:Panel runat="server" Title="Editor Panel">
    <Items>
      <ext:Panel
        ID="Panel1"
        runat="server"
        Width="610"
        Height="300"
        Html="Content"
        BodyPadding="6"
        Title="Editor panel">
        <TopBar>
          <ext:Toolbar runat="server">
            <Items>
              <ext:Button
                ID="Button3"
                runat="server"
                Text="Edit"
                Icon="Pencil">
                <Listeners>
                  <Click Handler="this.setDisabled(true);#{Button2}.setDisabled(false);#{PanelEditor}.startEdit(#{Panel1}.getBody());" />
                </Listeners>
              </ext:Button>
              <ext:Button
                ID="Button4"
                runat="server"
                Text="Save"
                Icon="Disk"
                Disabled="true">
                <Listeners>
                  <Click Handler="this.setDisabled(true);#{Button1}.setDisabled(false);#{PanelEditor}.completeEdit();" />
                </Listeners>
              </ext:Button>
            </Items>
          </ext:Toolbar>
        </TopBar>
      </ext:Panel>
      <ext:Editor
        ID="Editor1"
        runat="server"
        HtmlDecode="true"
        UseHtml="true"
        AutoSize="true"
        Alignment="tl-tl?"
        AllowBlur="false"
        Shadow="False">
        <AutoSizeConfig Width="BoundEl" Height="BoundEl" />
        <Field>
          <ext:HtmlEditor ID="HTMLEditor1" runat="server" />
        </Field>
        <Listeners>
          <StartEdit Handler="this.field.iframeEl.setHeight(this.field.getHeight() - this.field.getToolbar().getHeight() - 4); this.field.textareaEl.setHeight(this.field.getHeight() - this.field.getToolbar().getHeight() - 4);" Delay="10" />
        </Listeners>
      </ext:Editor>
    </Items>
    <Listeners>
      <Deactivate Handler="#{Button1}.setDisabled(false);#{Button2}.setDisabled(true);#{PanelEditor}.completeEdit();" />
    </Listeners>
  </ext:Panel>
I have tried:
<DirectEvents>
  <Complete OnEvent="CompleteEdit">
    <ExtraParams>
     <ext:Parameter Name="HTMLContent" Value="#{HTMLEditor1}.getValue();" Mode="Raw" />
    </ExtraParams>
  </Complete> 
                   </DirectEvents>
and get a NullReferenceException. What am I doing wrong?