Move items from one DropDownList to other one

In this blog we will know how to move items from one DropDownList to other one.

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<title>Untitled Page</title>

</head>

<body>

<div>

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

<asp:Button ID="Button1" runat="server" Text="<|" onclick="Button1_Click" />

<asp:Button ID="Button2" runat="server" Text="|>" onclick="Button2_Click" />

<asp:Button ID="Button3" runat="server" Text="<<|" onclick="Button3_Click" />

<asp:Button ID="Button4" runat="server" Text="|>>" onclick="Button4_Click" />

<asp:DropDownList ID="DropDownList2" runat="server"> </asp:DropDownList>

</div>

</form>

</body>

</html>

using System;

using System.Configuration;

using System.Data;

using System.Linq;

using System.Web;

using System.Web.Security;

using System.Web.UI;

using System.Web.UI.HtmlControls;

using System.Web.UI.WebControls;

using System.Web.UI.WebControls.WebParts;

using System.Xml.Linq;

public partial class _Default : System.Web.UI.Page

{

protected void Page_Load(object sender, EventArgs e)

{

if (!IsPostBack)

{

DropDownList1.Items.Add("Raj");

DropDownList1.Items.Add("Ravi");

DropDownList1.Items.Add("Rahul");

DropDownList1.Items.Add("Raju");

DropDownList1.Items.Add("Rohit");

DropDownList1.Items.Add("Rajesh");

}

protected void Button1_Click(object sender, EventArgs e)

{

DropDownList1.Items.Add(DropDownList2.SelectedItem.Text);

int i = 0;

i = DropDownList2.SelectedIndex;

DropDownList2.Items.RemoveAt(i);

}

protected void Button2_Click(object sender, EventArgs e)

{

DropDownList2.Items.Add(DropDownList1.SelectedItem.Text);

int i = 0;

i = DropDownList1.SelectedIndex;

DropDownList1.Items.RemoveAt(i);

}

protected void Button3_Click(object sender, EventArgs e)

{

int j = 0;

for (j = 0; j <= DropDownList2.Items.Count - 1; j++)

{

DropDownList1.Items.Add(DropDownList2.Items[j]);

}

DropDownList2.Items.Clear();

}

protected void Button4_Click(object sender, EventArgs e)

{

int j = 0;

for (j = 0; j <= DropDownList1.Items.Count - 1; j++)

{

DropDownList2.Items.Add(DropDownList1.Items[j]);

}

DropDownList1.Items.Clear();

}