Run events based on start and end time in ASP.Net using C# and VB.Net

Hi RichardSa,

Use Ajax timer control to check the time.

Refer below example.

HTML

<asp:ScriptManager runat="server" />
<asp:UpdatePanel runat="server">
    <ContentTemplate>
        <asp:Timer ID="timer1" runat="server" OnTick="timer1_Tick" Interval="1000"></asp:Timer>
        <asp:Label ID="lblTime" runat="server" />
    </ContentTemplate>
</asp:UpdatePanel>

Code

C#

protected void timer1_Tick(object sender, EventArgs e)
{
    DateTime startTime = new DateTime(2021, 08, 19, 16, 50, 00);
    DateTime endTime = new DateTime(2021, 08, 19, 18, 05, 00);
    if (DateTime.Now > startTime && DateTime.Now < endTime)
    {
        // Do your task.
        lblTime.Text = DateTime.Now.ToString();
    }
}

VB.Net

Protected Sub timer1_Tick(ByVal sender As Object, ByVal e As EventArgs)
    Dim startTime As DateTime = New DateTime(2021, 08, 19, 16, 50, 00)
    Dim endTime As DateTime = New DateTime(2021, 08, 19, 18, 05, 00)

    If DateTime.Now > startTime AndAlso DateTime.Now < endTime Then
        lblTime.Text = DateTime.Now.ToString()
    End If
End Sub