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<%@ Page language="c#" autoeventwireup="false" %>

<html>
<head>
<title>Chapter 6: ASP.NET List Controls</title>
<script language="C#" runat="server">
    
private void AddButton_Click(object sender, EventArgs e)
{
    ListItem NewItem = new ListItem(ItemText.Text);
    if(!ItemList.Items.Contains(NewItem)){
        ItemList.Items.Add(ItemText.Text);
    }
}

</script>

</head>
<body>

    <form runat="server">
        <h3>Using CheckBoxList</h3>
        <h4>Adding items with the Add method</h4>
        Item Text:<br>
        <asp:textbox id="ItemText" runat="Server" />
        <asp:button text="Add" runat="server" ID="AddButton" onclick="AddButton_Click"/>
        <br>
        <asp:checkboxlist id="ItemList" runat="server"/>

    </form>

</body>
</html>