在ASP.NET中5秒后重置窗体和页面状态

Question

I have a form that the user submits and gets a Success -message. Now I need to redirect back to the form and empty it , but I cannot seem to get the page to refresh itself after 5 seconds.

This is what I've got so far. With this I get Response is not available in this context , which means I need some other way to refresh.

protected void bSubmit_Click(object sender, EventArgs e)
    lblFeedback.Text = "Your message has been sent.";
    lblFeedback.Visible = true; // Show the success-message
    mainForm.Visible = false; // Hide the form the user just filled in

    reTimer = new System.Timers.Timer(1000 * 5);
    reTimer.Elapsed += new System.Timers.ElapsedEventHandler(RefreshToForm);
    reTimer.Enabled = true;
}

private void RefreshToForm(object sender, System.Timers.ElapsedEventArgs e)
{
    reTimer.Enabled = false;
    reTimer = null;
    Response.Redirect(Request.RawUrl);
}

Answer 1

Try adding a Refresh header in the Response instead of using a Timer:

protected void bSubmit_Click(object sender, EventArgs e)
    lblFeedback.Text = "Your message has been sent.";
    lblFeedback.Visible = true; // Show the success-message
    mainForm.Visible = false; // Hide the form the user just filled in

    Response.AddHeader("Refresh", "5"); // Refresh the page after 5 seconds
}

Answer 2

A server-side timer won't work - by the time it triggers, the request has probably already finished and returned to the client, hence why you can't get the Request object, it's out of context.

One option is to simply clear all the form controls out, rather than waiting and then refreshing (I imagine that's a bit confusing for the user, plus it will destroy your "Feedback" message, which they might not see if they don't immediately look at the page within 5 seconds).

Here's one I made earlier:

/// <summary>
/// Reset input fields within a collection of Controls back to their empty/cleared states
/// </summary>
/// <param name="ctrls"></param>
/// <remarks>Will clear textboxes, dropdownlists and checkboxes. Checkboxes will be reset to un-checked.</remarks>
private void ClearInputs(ControlCollection ctrls)
{
  foreach (Control ctrl in ctrls) {
    if (ctrl is TextBox) {
        ((TextBox)ctrl).Text = string.Empty;
    } else if (ctrl is DropDownList) {
        ((DropDownList)ctrl).ClearSelection();
    } else if (ctrl is CheckBox) {
        ((CheckBox)ctrl).Checked = false;
    } else if (ctrl is HiddenField) {
        ((HiddenField)ctrl).Value = string.Empty;
    }

    ClearInputs(ctrl.Controls);
  }
}

In your case, you can call it like this:

ClearInputs(mainForm.Controls);