In this article I will explain with an example, how to add Default Item (Initial Value) to DropDownList populated using SqlDataSource in ASP.Net.
Generally we want to have a default selected item such as Please Select. This article will explain how to add such default item when DropDownList is populated using SqlDataSource.
Database
Here I am making use of Microsoft’s Northwind Database. The download and install instructions are provided in the following article.
DropDownList control and its Properties
DataSourceID – The ID of the
SqlDataSource control is set as value to this property, this way the
DropDownList control determines its source of data.
DataTextField – The name of the column to be set as Text in
DropDownList. These values will be visible to end user.
DataValueField – The name of the column to be set as Value in
DropDownList. These values will not be visible to end user.
AppendDataBoundItems – This property if set True then it will not clear the existing
DropDownList values instead it will append the values from Database.
This property must be set to True when the
DropDownList needs to display a default item such as Please select, etc.
HTML Markup
The SqlDataSource control is set with the following properties.
1.
ConnectionString – Name of the Connection String setting in the
Web.Config file.
2. SelectCommand – The Select statement to fetch the records from the Employees table of the Northwind database.
The ID of the
SqlDataSource control is set as
DataSourceID of the
DropDownList control.
The default item is added to the
DropDownList by placing a
ListItem and setting the
AppendDataBoundItems property to True.
<asp:DropDownList ID="ddlEmployees" runat="server" DataSourceID="SqlDataSource1"
DataTextField="EmployeeName" DataValueField="EmployeeID" AppendDataBoundItems="true">
<asp:ListItem Text="Please select" Value="" />
</asp:DropDownList>
<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:constr %>"
SelectCommand="SELECT (FirstName + ' ' + LastName) AS EmployeeName, EmployeeID FROM Employees">
</asp:SqlDataSource>
Screenshot
Demo
Downloads