How to select all records in a DropDownList

Question

I have this DropDownList:

Answer 1

following is the way to bind DropDownList from codebehind. visit this link for details

 <asp:DropDownList ID="DropDownList1" runat="server">
 </asp:DropDownList>

CODE BEHIND

SqlConnection con = new SqlConnection(str);
string com = "select * all from tbl_Cat";
SqlDataAdapter adpt = new SqlDataAdapter(com, con);
DataTable dt = new DataTable();
adpt.Fill(dt);

DropDownList1.DataSource = dt;
DropDownList1.DataBind();
DropDownList1.DataTextField = "Categorie";
DropDownList1.DataValueField = "Cat_ID";
DropDownList1.DataBind();

Answer 2

You need to write the below code which help you to select all option for category.

 <asp:DropDownList ID="DropDownList1" AutoPostBack="true" runat="server">
 </asp:DropDownList>

In Code behind file

SqlConnection con = new SqlConnection(str);
string com = "select * all from tbl_Cat";
SqlDataAdapter adpt = new SqlDataAdapter(com, con);
DataTable dt = new DataTable();
adpt.Fill(dt);

DropDownList1.DataSource = dt;
DropDownList1.DataBind();
DropDownList1.DataTextField = "Categorie";
DropDownList1.DataValueField = "Cat_ID";
DropDownList1.DataBind();
DropDownList1.Items.Insert(0, new ListItem("Select ALL", "0"));

Now you can check if drop down selected value is 0, if it is 0 then you can load all the records in the grid.

Let me know if any thing i miss.

Answer 3

May be you have this query,

DropDownList1.Items.Add(new ListItem("Select All", "0"));