Disable Dropdownlist some items based on condition in asp.net

In this article I am going to explain how to disable Dropdownlist some items based on condition in asp.net using C#, VB.net

In the previous article I have explained how to remove the selected item fromdropdownlist in asp.net using C#, VB.net, how to show the data in Gridviewclient side using Jquery, Json and Ajax and how to populate Category andSub-category in single dropdownlist in Asp.net.

Implementation:

HML Markup:

<asp:DropDownList ID="ddlItems" runat="server" CssClass="dropdownlist" AutoPostBack="true" >

         <asp:ListItem Selected="True" Value="-1">--Select Item--</asp:ListItem>

            <asp:ListItem>Item 1</asp:ListItem>

            <asp:ListItem>Item 2</asp:ListItem>

            <asp:ListItem>Item 3</asp:ListItem>

            <asp:ListItem>Item 4</asp:ListItem>

            <asp:ListItem>Item 5</asp:ListItem>             

        </asp:DropDownList>

Disable dropdownlist item

To disable the dropdownlist  some item create a method and  call it on page load.

C# Code:

protected void Page_Load(object sender, EventArgs e)

    {

        if (!IsPostBack)

        {

            DisableDropdownItem();

        }     

    }

protected void DisableDropdownItem()

    {

        try

        {

            foreach (ListItem item in ddlItems.Items)

            {

                if (item.Text == "Item 1" || item.Text == "Item 4")

                {

                    item.Attributes.Add("disabled", "disabled");

                }

            }

        }

        catch (Exception ex)

        {

        }       

    }

VB.net Code:

Protected Sub Page_Load(sender As Object, e As System.EventArgs) Handles Me.Load

        If Not IsPostBack Then

         DisableDropdownItem()

        End If

    End Sub

  Protected Sub DisableDropdownItem()

        Try

            For Each item As ListItem In ddlItems.Items

                If item.Text = "Item1" OrElse item.Text = "Item4" Then

                    item.Attributes.Add("disabled", "disabled")

                End If

            Next

        Catch ex As Exception

        End Try

    End Sub