Menus

Tuesday, December 4, 2012

Programmatically Select Multiple Items of an ASP.NET ListBox

In one of the forums, a user recently asked how to select multiple items of an ASP.NET ListBox. Here’s how
<div>
    <asp:ListBox ID="ListBox1" runat="server">
        <asp:ListItem Value="One" />
        <asp:ListItem Value="Two" />
        <asp:ListItem Value="Three" />
        <asp:ListItem Value="Four" />
        <asp:ListItem Value="Five" />
    </asp:ListBox>
</div>    
C#
protected void Page_Load(object sender, EventArgs e)
{
    ListBox1.SelectionMode = ListSelectionMode.Multiple;
    for (int i = 0; i < ListBox1.Items.Count; i++)
    {
        if(i == 0 || i == 2 || i == 4)
        {
            ListBox1.Items[i].Selected = true;
        }
    }
}
VB.NET
Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
    ListBox1.SelectionMode = ListSelectionMode.Multiple
    For i As Integer = 0 To ListBox1.Items.Count - 1
        If i = 0 OrElse i = 2 OrElse i = 4 Then
            ListBox1.Items(i).Selected = True
        End If
    Next i
End Sub
The code shown above selects the first, third and fifth items of a ListBox as in the screenshot below
image

No comments:

Post a Comment