Select Decimal point based on DropDownList selected value using C# and VB.Net in ASP.Net

Hi fahimahmed,

Check this example. Now please take its reference and correct your code.

HTML

<asp:TextBox runat="server" ID="txtUnitPriceLocal" Text="4434.3245494" />
<asp:DropDownList ID="ddlRoundDecimals" runat="server" OnSelectedIndexChanged="Round"
    AutoPostBack="true">
    <asp:ListItem Value="0" Text="Select" />
    <asp:ListItem Value="1" Text="1" />
    <asp:ListItem Value="2" Text="2" />
    <asp:ListItem Value="3" Text="3" />
    <asp:ListItem Value="4" Text="4" />
    <asp:ListItem Value="5" Text="5" />
    <asp:ListItem Value="6" Text="6" />
</asp:DropDownList>
<hr />
<asp:Label ID="lblUnitPriceLocal" runat="server" />

Code

C#

protected void Round(object sender, EventArgs e)
{
    decimal UnitPriceLocal_Round = Convert.ToDecimal(txtUnitPriceLocal.Text);
    UnitPriceLocal_Round = Math.Round(UnitPriceLocal_Round, int.Parse(ddlRoundDecimals.SelectedValue));
    lblUnitPriceLocal.Text = UnitPriceLocal_Round.ToString();
}

VB.Net

Protected Sub Round(ByVal sender As Object, ByVal e As EventArgs)
    Dim UnitPriceLocal_Round As Decimal = Convert.ToDecimal(txtUnitPriceLocal.Text)
    UnitPriceLocal_Round = Math.Round(UnitPriceLocal_Round, Integer.Parse(ddlRoundDecimals.SelectedValue))
    lblUnitPriceLocal.Text = UnitPriceLocal_Round.ToString()
End Sub

Screenshot