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How to enable and disable a DropDownList programmatically

Enable and Disable DropDownList programmatically
dropdownlist is an asp.net list web server control. this control allow the users to select a single item at a time. .net developers dynamically enable or disable a dropdownlist control within a web page depending on various criteria. the following c# example source code demonstrate us how can we enabled a disabled dropdownlist or disabled a enabled dropdownlist programmatically at run time in asp.net. code explain how developers can switch between dropdownlist enabled and disabled state dynamically.

dropdownlist Enabled property get or set a value that indicate whether dropdownlist server control is enabled. this property accept a boolean value. by setting its value True we can enable a disabled dropdownlist. and by using its value False we can disable a dropdownlist in web page. disable states dropdownlist typically appears dimmed in browser user interface.
DropDownListDisable.aspx

<%@ Page Language="C#" %>

<!DOCTYPE html>

<script runat="server">
    protected void Button1_Click(object sender, System.EventArgs e)
    {
        DropDownList1.Enabled = false;
    }
    protected void Button2_Click(object sender, System.EventArgs e)
    {
        DropDownList1.Enabled = true;
    }
</script>

<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
    <title>How to enable, disable DropDownList programmatically</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <h2 style="color:Navy">DropDownList: Enable, Disable</h2>
        <asp:Label 
             ID="Label1"
             runat="server"
             Font-Bold="true"
             ForeColor="IndianRed"
             Text="asp.net controls"
             >
        </asp:Label>
        <asp:DropDownList 
             ID="DropDownList1"
             runat="server"
             >
             <asp:ListItem>ConnectionsZone</asp:ListItem>
             <asp:ListItem>LoginView</asp:ListItem>
             <asp:ListItem>SiteMapPath</asp:ListItem>
             <asp:ListItem>ListBox</asp:ListItem>
             <asp:ListItem>LayoutEditorPart</asp:ListItem>
        </asp:DropDownList>
        <br /><br />
        <asp:Button 
             ID="Button1"
             runat="server"
             Font-Bold="true"
             ForeColor="IndianRed"
             Text="Disable DropDownList"
             OnClick="Button1_Click"
             />
        <asp:Button 
             ID="Button2"
             runat="server"
             Font-Bold="true"
             ForeColor="IndianRed"
             Text="Enable DropDownList"
             OnClick="Button2_Click"
             />
    </div>
    </form>
</body>
</html>
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