Show Hide Panel based on ASP.Net DropDownList selection using C# and VB.Net

Hi micah,

Refer below code.

HTML

<div class="container">
    <asp:DropDownList ID="ddlmethode" runat="server"
        CssClass="form-control pro-edt-select form-control-primary" Width="100%"
        AutoPostBack="true" OnSelectedIndexChanged="DropDownList_Changed">
        <asp:ListItem Text="--Select Payment Method--" Value="C" />
        <asp:ListItem Text="Cash" Value="Ca" />
        <asp:ListItem Text="Cheque" Value="CH" />
        <asp:ListItem Text="Transfer" Value="TR" />
    </asp:DropDownList>
    <asp:Panel ID="pnlTextBox" runat="server" Visible="false">
        <asp:TextBox ID="txtbank" runat="server" CssClass="form-control" placeholder="Bank Name"></asp:TextBox>
    </asp:Panel>
</div>

Code

C#

protected void DropDownList_Changed(object sender, EventArgs e)
{
    pnlTextBox.Visible = false;
    if (ddlmethode.SelectedItem.Value == "CH" || ddlmethode.SelectedItem.Value == "TR")
    {
        pnlTextBox.Visible = true;
    }
}

VB.Net

Protected Sub DropDownList_Changed(ByVal sender As Object, ByVal e As EventArgs)
    pnlTextBox.Visible = False
    If ddlmethode.SelectedItem.Value = "CH" OrElse ddlmethode.SelectedItem.Value = "TR" Then
        pnlTextBox.Visible = True
    End If
End Sub

Screenshot