Question

I have following drop down

        <li><span>State: <asp:DropDownList ID="ddlAppState" runat="server">
                        </asp:DropDownList></span></li>

It gets populated on page load () using below function

          private void ddlAppState_DataBind()
{
    string myXMLfile = Server.MapPath("~/App_Data/ActiveStates.xml");
    System.Data.DataSet dsStudent = new System.Data.DataSet();

    dsStudent.ReadXml(myXMLfile);
    ddlAppState.DataSource = dsStudent;
    ddlAppState.DataValueField = "StateID";
    ddlAppState.DataTextField = "StateName";
    ddlAppState.DataBind();
}

Inititally the value in drop down is “——–” but on backend it maps to “FD” i want to validate if the “—–” is selected whose value if i get by doing ddlAppState.SelectedValue.ToString() is a string “FD” then i do not want to call the onlick function of button .

Button OnClick

 <asp:Button Style="left: 0px; position: relative" ID="btnSearch" runat="server" CausesValidation="False"
                CssClass="lbSearch closeform" Text="Search" Width="80px" OnClick="btnSearch_Click"  >
            </asp:Button></div>

 protected void btnSearch_Click(object sender, EventArgs e)
{
    try
    {
            if (ddlAppState.SelectedValue.ToString() == "FD" && ddlAppMode.SelectedValue.ToString() == "S")
      {
          SelectState.Text = " Please Select State ";
          return;
            }

            SelectState.Text = "";
        BindGridViewZipConfirmation1();

// clearFields();
}

Any idea of how it can be done . Thank You

Answer 1

You could check whether the SelectedIndex is greater than zero (the default value), then use SelectedValue if it is. Otherwise just return from the click handler.