[ASP.NET] GridView 排序符號

2010-08-11

摘要:[ASP.NET] GridView 排序符號

有時候有些客戶會要求在GridView上面有排序的功能，這對GridView來說實在太容易了，

只要GridView的AllowSorting="True"就可以使用這個功能了，

但是客戶常常會說可是都沒有符號，我怎麼知道他是怎麼排，

可是偏偏微軟就是沒提供這個功能，就只好自己來了，

我把他寫成一個簡單的副程式

Public Sub GridViewSorting(ByVal sender As Object, ByVal e As GridViewSortEventArgs)

'此程式為增加升降冪符號在GridView中，GridView的事件狀態為Sorting

If ViewState("SortDir") Is Nothing Then

ViewState("SortDir") = SortDirection.Descending

End If

'把所有的符號清掉

For i As Integer = 0 To DirectCast(sender, GridView).Columns.Count - 1

DirectCast(sender, GridView).Columns(i).HeaderText = DirectCast(sender, GridView).Columns(i).HeaderText.Replace("▲", "")

DirectCast(sender, GridView).Columns(i).HeaderText = DirectCast(sender, GridView).Columns(i).HeaderText.Replace("▼", "")

Dim ViewState_SortDirection As String = ViewState("SortDir").ToString() '定義GridView的升降冪

Dim Columns_i As Integer = 0

For i As Integer = 0 To DirectCast(sender, GridView).Columns.Count - 1

If e.SortExpression = DirectCast(sender, GridView).Columns(i).SortExpression Then '找出現在的Columns

Columns_i = i

If ViewState("SortDir").ToString() = SortDirection.Ascending.ToString() Then '若為升冪

e.SortDirection = SortDirection.Descending

DirectCast(sender, GridView).Columns(i).HeaderText = DirectCast(sender, GridView).Columns(i).HeaderText & "▼"

ViewState("SortDir") = SortDirection.Descending

Else '若其他則為降冪

e.SortDirection = SortDirection.Ascending

DirectCast(sender, GridView).Columns(i).HeaderText = DirectCast(sender, GridView).Columns(i).HeaderText & "▲"

ViewState("SortDir") = SortDirection.Ascending

End If

End Sub

然後呼叫在GridView.Sorting的事件中參考你所要做排序的GridView就可以了

Protected Sub GridView1_Sorting(ByVal sender As Object, ByVal e As GridViewSortEventArgs) Handles GridView1.Sorting

Me.GridViewSorting(Me.GridView1, e)

End Sub