常用功能:在ListBox间移动Items,改变Items的顺序

刚刚为了解决一个问题写了一个比较常用的功能:从一个ListBox中选择(转移)Items到另一个ListBox,改变Items在ListBox中的顺序.
截图如下:


实现代码如下:

<% @ Page Language="VB"  %>

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

< script  runat ="server" >

    Protected Sub btnMoveUp_Click(ByVal sender As Object, ByVal e As System.EventArgs)
        Dim Item As New ListItem
        Dim PrevIndex As Integer
        'Move sites order of preference in up direction
        If lstSelectedSites.GetSelectedIndices.Length = 1 Then
            If lstSelectedSites.SelectedIndex <> -1 Then

                Item.Value = lstSelectedSites.SelectedValue
                Item.Text = lstSelectedSites.SelectedItem.ToString
                PrevIndex = CInt(lstSelectedSites.SelectedIndex) - 1
                If PrevIndex = -1 Then
                    Exit Sub
                End If
                lstSelectedSites.Items.Remove(lstSelectedSites.SelectedItem)
                lstSelectedSites.Items.Insert(PrevIndex, Item.Text)
                lstSelectedSites.Items.Item(PrevIndex).Value = Item.Value
                lstSelectedSites.SelectedIndex = PrevIndex

            End If
        End If
    End Sub

    Protected Sub btnMoveDown_Click(ByVal sender As Object, ByVal e As System.EventArgs)
        Dim Item As New ListItem
        Dim NextIndex As Integer
        'Move sites order of preference in up direction
        If lstSelectedSites.GetSelectedIndices.Length = 1 Then
            If lstSelectedSites.SelectedIndex <> -1 Then

                Item.Value = lstSelectedSites.SelectedValue
                Item.Text = lstSelectedSites.SelectedItem.ToString
                NextIndex = CInt(lstSelectedSites.SelectedIndex) + 1
                If NextIndex = lstSelectedSites.Items.Count Then
                    Exit Sub
                End If
                lstSelectedSites.Items.Remove(lstSelectedSites.SelectedItem)
                lstSelectedSites.Items.Insert(NextIndex, Item.Text)
                lstSelectedSites.Items.Item(NextIndex).Value = Item.Value
                lstSelectedSites.SelectedIndex = NextIndex

            End If
        End If
    End Sub

    Protected Sub btnSelect_Click(ByVal sender As Object, ByVal e As System.EventArgs)
        Dim Item As New ListItem
        Dim j As Integer = lstAllSites.GetSelectedIndices().Length
        'Move sites order of preference in up direction
        If j > 0 Then
            Dim i As Integer
            i = 0
            Do While (i < j)
                lstSelectedSites.Items.Insert(lstSelectedSites.Items.Count, lstAllSites.Items.Item(lstAllSites.GetSelectedIndices(i)))
                lstAllSites.Items.Remove(lstAllSites.Items.Item(lstAllSites.GetSelectedIndices(i)))
                j -= 1
            Loop
        End If
    End Sub

    Protected Sub btnUnSelect_Click(ByVal sender As Object, ByVal e As System.EventArgs)
        Dim Item As New ListItem
        Dim j As Integer = lstSelectedSites.GetSelectedIndices().Length
        'Move sites order of preference in up direction
        If j > 0 Then
            Dim i As Integer
            i = 0
            Do While (i < j)
                lstAllSites.Items.Insert(lstAllSites.Items.Count, lstSelectedSites.Items.Item(lstSelectedSites.GetSelectedIndices(i)))
                lstSelectedSites.Items.Remove(lstSelectedSites.Items.Item(lstSelectedSites.GetSelectedIndices(i)))
                j -= 1
            Loop
        End If
    End Sub
</ script >

< html  xmlns ="http://www.w3.org/1999/xhtml" >
< head  id ="Head1"  runat ="server" >
     < title > Untitled Page </ title >
</ head >
< body >
     < form  id ="form1"  runat ="server" >
     < div >
         < asp:ScriptManager  ID ="ScriptManager1"  runat ="server" >
         </ asp:ScriptManager >
         < asp:UpdatePanel  ID ="UpdatePanel1"  runat ="server"  UpdateMode ="Conditional"  
            ChildrenAsTriggers ="False" >
             < ContentTemplate >
                 < table  style ="width: 100%;" >
                     < tr >
                         < td >
                             < asp:UpdatePanel  UpdateMode ="Conditional"  ID ="UPanellstAllSites"  runat ="server" >
                                 < ContentTemplate >
                                     < asp:ListBox  BorderStyle ="None"  BackColor ="white"  ID ="lstAllSites"  runat ="server"
                                        Height ="251px"  Width ="258px"  Style ="border: none;"  SelectionMode ="Multiple" >
                                         < asp:ListItem  Value ="1"  Text ="1"   />
                                         < asp:ListItem  Value ="2"  Text ="2"   />
                                         < asp:ListItem  Value ="3"  Text ="3"   />
                                         < asp:ListItem  Value ="4"  Text ="4"   />
                                         < asp:ListItem  Value ="5"  Text ="5"   />
                                         < asp:ListItem  Value ="6"  Text ="6"   />
                                         < asp:ListItem  Value ="7"  Text ="7"   />
                                         < asp:ListItem  Value ="8"  Text ="8"   />
                                         < asp:ListItem  Value ="9"  Text ="9"   />
                                         < asp:ListItem  Value ="10"  Text ="10"   />
                                     </ asp:ListBox >
                                 </ ContentTemplate >
                             </ asp:UpdatePanel >
                         </ td >
                         < td >
                             < asp:Button  ID ="btnSelect"  runat ="server"  Text ="Select"  OnClick ="btnSelect_Click"   />
                             < asp:Button  ID ="btnMoveUp"  runat ="server"  Text ="MoveUp"  OnClick ="btnMoveUp_Click"   />
                             < asp:Button  ID ="btnMoveDown"  runat ="server"  Text ="MoveDown"  OnClick ="btnMoveDown_Click"   />
                             < asp:Button  ID ="btnUnSelect"  runat ="server"  Text ="UnSelect"  OnClick ="btnUnSelect_Click"   />
                         </ td >
                         < td >
                             < asp:UpdatePanel  UpdateMode ="Conditional"  ID ="UpdatePanel2"  runat ="server" >
                                 < ContentTemplate >
                                     < asp:ListBox  BorderStyle ="None"  ID ="lstSelectedSites"  runat ="server"  Height ="291px"
                                        Width ="258px"  Style ="background-color: #c6c6ce; border: none; text-decoration: none;
                                        text-align: center;"  SelectionMode ="Multiple" ></ asp:ListBox >
                                 </ ContentTemplate >
                                 < Triggers >
                                     < asp:AsyncPostBackTrigger  ControlID ="btnMoveDown"   />
                                     < asp:AsyncPostBackTrigger  ControlID ="btnMoveUp"   />
                                 </ Triggers >
                             </ asp:UpdatePanel >
                         </ td >
                     </ tr >
                 </ table >
             </ ContentTemplate >
             < Triggers >
                 < asp:AsyncPostBackTrigger  ControlID ="btnSelect"   />
                 < asp:AsyncPostBackTrigger  ControlID ="btnUnSelect"   />
             </ Triggers >
         </ asp:UpdatePanel >
     </ div >
     </ form >
</ body >
</ html >

这个功能在Winform里很常用的.