how to add the days in current date using asp.net [closed]

Question

i want to add the days to the current date for example i want to input the days in digits and than i select the days in which i want to add in current date means days, weeks and month but when i select the days or weeks or month it shows the days but can not add them in current date can any one help me plz

 protected void TextBoxPredictDays_TextChanged(object sender, EventArgs e)
        {
            string selectPredictDays = DropDownList1.SelectedItem.Value;
            String Days1;
            int Result;
            Days1 = TextBoxPredictedClosing.ToString();
            if (selectPredictDays == "Days")
            {

                Result = Convert.ToInt32(TextBoxPredictDays.Text) * 1;
                TextBoxPredictedClosing.Text = Result.ToString();

            }
            else if (selectPredictDays == "Weeks")
            {

                Result = Convert.ToInt32(TextBoxPredictDays.Text) * 7;
                TextBoxPredictedClosing.Text = Result.ToString();
            }
            else if (selectPredictDays == "Months")
            {

                Result = Convert.ToInt32(TextBoxPredictDays.Text) * 30;
                TextBoxPredictedClosing.Text = Result.ToString();
            }

        }

here is my design code

 <asp:TextBox ID="TextBoxPredictDays" runat="server" 
            ontextchanged="TextBoxPredictDays_TextChanged"  Width="101px" Height="14px" ></asp:TextBox>
      <asp:DropDownList ID="DropDownList1" runat="server" 
            onselectedindexchanged="DropDownList1_SelectedIndexChanged">
            <asp:ListItem>Days</asp:ListItem>
            <asp:ListItem>Weeks</asp:ListItem>
            <asp:ListItem>Months</asp:ListItem>
        </asp:DropDownList>

Answer 1

DateTime.Now.AddDays(int) - for days
DateTime.Now.AddDays(int * 7) - for weeks
DateTime.Now.AddMonths(int) - for months

Answer 2

DateTime dt = DateTime.Now.AddDays(int); Days
dt = DateTime.Now.AddMonths(int);  Months
dt = DateTime.Now.AddDays(int * 7); Week

Answer 3

This is what your method would look like:

protected void TextBoxPredictDays_TextChanged(object sender, EventArgs e)
        {
            string selectPredictDays = DropDownList1.SelectedItem.Value;
            if (selectPredictDays == "Days")
            {
                TextBoxPredictedClosing.Text = DateTime.Now.AddDays(Convert.ToInt32(TextBoxPredictDays.Text));
            }
            else if (selectPredictDays == "Weeks")
            {
                TextBoxPredictedClosing.Text = DateTime.Now.AddDays(Convert.ToInt32(TextBoxPredictDays.Text) * 7);
            }
            else if (selectPredictDays == "Months")
            {
                TextBoxPredictedClosing.Text = DateTime.Now.AddMonths(Convert.ToInt32(TextBoxPredictDays.Text));
            }
        }