C#

public class CusParamTextBox : BaseParam
{
   public event EventHandler ExposedUpdate;
   
   protected virtual void OnExposedUpdate(EventArgs e)
   {
      var handler = ExposedUpdate;
      if (handler != null) handler(this, e);
   }
   
   ...
   
   private void ParamTxtBox_TextChanged(object sender, EventArgs e)
   {
      ...
      OnExposedUpdate(e);
   }
}

...

var tmpctrlx = new CusParamTextBox();
tmpctrlx.ExposedUpdate += Update;

...

protected void Update(object sender, EventArgs e)
{
   var cuscontrol = (CusParamTextBox)sender;
   DoSomethingOnPage(cuscontrol.name, cuscontrol.value);
   upMain.Update();
}

<asp:UpdatePanel runat="server" UpdateMode="Conditional">
  <ContentTemplate>
     <uc:CusParamTextBox ID="CusParamTextBox1" runat="server" OnExposedUpdate="Update" />
  </ContentTemplate>
  <Triggers>
    <asp:AsyncPostBackTrigger ControlID="CusParamTextBox1" EventName="ExposedUpdate" />
  </Triggers>
</asp:UpdatePanel>

CusParamTextBox tmpctrlx = new CusParamTextBox();
tmpctrlx.ExposedUpdate += new EventHandler(UpdateText);
ScriptManager1.RegisterAsyncPostBackControl(tmpctrlx);
CusParamControls.Controls.Add(tmpctrlx);

<asp:UpdatePanel runat="server" ID="upMain" Visible="true" ChildrenAsTriggers="true" UpdateMode="Conditional">
    <ContentTemplate>
        <asp:Panel runat="server" ID="CusParamControls"></asp:Panel>
    </ContentTemplate>
</asp:UpdatePanel>

protected override void OnInit(EventArgs e)
{
base.OnInit(e);

ScriptManager script = ScriptManager.GetCurrent(Page);
TxtParamValue = new TextBox();
TxtParamValue.TextChanged += new EventHandler(TxtParamValue_TextChanged);
if (script != null) { script.RegisterAsyncPostBackControl(TxtParamValue);}
base.Controls.Add(TxtParamValue);
}

dsshiny wrote:

Is it possible to digitally sign a PDF file using USB token through C# program?

dsshiny wrote:

If yes, please give me sample code ..

Bastard Programmer from Hell
If you can't read my code, try converting it here[^]