I need to show loading message in asp.net webforms-CodePudding

I am using asp.net webforms. On button click I am calling api which blocks code. I am doing this from code behind. This function needs few seconds to complete. During this time I would like to show loading message. I have trouble with this.

I think I should somehow incorporate javascript/jquery, but was unable to to this successfully(was trying to use jquery blockUI).

CodePudding user response：

Since the user is clicking a button to run that code behind?

A button can have both a client-side event, and the server-side code behind.

So, simple have some client-side code run, display "spinner" in a "div" or some please wait message.

That "div" or spinner image will thus display. The really nice part, since the button is a post-back, when the button code behind is done, then your page will re-fresh, and the spinner/message will thus disappear all on its own.

Say I have a grid view I want to load with a button press. Thus, this markup:

        <asp:GridView ID="GridView1" runat="server" CssClass="table"
            Width="45%" DataKeyNames="ID">
        </asp:GridView>
        <br />
        <asp:Button ID="cmdLoadData" runat="server" Text="Load Data"
            CssClass="btn"
            OnClick="cmdLoadData_Click"
            OnClientClick="$('#myspindiv').show();"
            />

        <div id="myspindiv" style="display:none">
            <h2>Loading data -- please wait"</h2>
            <img src="../Content/wait2.gif" />
        </div>

So, you can drop/have/place whatever you want in the above "div" for the wait message. (but, note the style=display:none to hide it).

Note how the button code has both a server-side event, and a client side click event.

Code behind is this:

protected void cmdLoadData_Click(object sender, EventArgs e)
{
    string strSQL = "SELECT * FROM VHotelsA ORDER BY HotelName";
    using (SqlConnection conn = new SqlConnection(Properties.Settings.Default.TEST4))
    {
        using (SqlCommand cmdSQL = new SqlCommand(strSQL, conn))
        {
            conn.Open();
            DataTable rstData = new DataTable();
            rstData.Load(cmdSQL.ExecuteReader());
            GridView1.DataSource = rstData;
            GridView1.DataBind();

            // FAKEa  3 second delay
            System.Threading.Thread.Sleep(3000);

        }
    }
}

So, the result is now this: