topcat 姍舞之間的極度凝聚

Public Class MyRegionObj
    Private m_RegionID As Decimal
    Private m_RegionDescription As String

    Public Property RegionID() As Decimal
        Get
            Return m_RegionID
        End Get
        Set(ByVal value As Decimal)
            m_RegionID = value
        End Set
    End Property

    Public Property RegionDescription() As String
        Get
            Return m_RegionDescription
        End Get
        Set(ByVal value As String)
            m_RegionDescription = value
        End Set
    End Property
End Class

'宣告事件的Handler，注意第二個參數透過ByReference的方式
'透過ByReference可以傳遞回來處理
Public Delegate Sub Region_GetDataHandler(ByVal sender As Object, ByRef myRegion As MyRegionObj)

Public Interface IEvntMode001
    Event GetData As Region_GetDataHandler
End Interface

<hr />
Region:<asp:Label ID="lblRegion" runat="server" Text=""></asp:Label><br />
RegionDescription:<asp:Label ID="lblRegionDescription" runat="server" Text=""></asp:Label><br />
<asp:Button ID="btnGet" runat="server" Text="取得資料" />

Partial Class wucEvent001
    Inherits System.Web.UI.UserControl

    'Implement介面
    Implements IEvntMode001

    '宣告要傳遞的物件類別
    Private myRegion As MyRegionObj

    Public Event GetData(ByVal sender As Object, ByRef myRegion As MyRegionObj) Implements IEvntMode001.GetData

    Protected Sub btnGet_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnGet.Click
        '觸發事件,傳送wuc本身，以及myRegion這個物件類別
        '其中myRegion是透過ByReference的方式傳遞，到時候也透過這個把資料傳回
        RaiseEvent GetData(Me, myRegion)

        '如果運作後傳遞回來的物件類別有執行個體(不是Notiong)
        '就可以把物件類別中的資料放到Label
        If myRegion IsNot Nothing Then
            Me.lblRegion.Text = myRegion.RegionID.ToString
            Me.lblRegionDescription.Text = myRegion.RegionDescription
        End If
    End Sub
End Class

<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False"
    DataKeyNames="RegionID" DataSourceID="SqlDataSource1" EmptyDataText="沒有資料錄可顯示。">
    <Columns>
        <asp:BoundField DataField="RegionID" HeaderText="RegionID" ReadOnly="True"
            SortExpression="RegionID" />
        <asp:BoundField DataField="RegionDescription" HeaderText="RegionDescription"
            SortExpression="RegionDescription" />
        <asp:TemplateField>
            <ItemTemplate>
                <asp:HiddenField ID="hidRegionID" runat="server" Value='<%#Eval("RegionID") %>' />
                <asp:HiddenField ID="hidRegionDescription" runat="server" Value='<%#Eval("RegionDescription") %>' />
                <uc1:wucEvent001 ID="wucEvent0011" runat="server" OnGetData="GetData" />
            </ItemTemplate>
        </asp:TemplateField>
    </Columns>
</asp:GridView>
<asp:SqlDataSource ID="SqlDataSource1" runat="server"
    ConnectionString="<%$ ConnectionStrings:NorthwindConnectionString1 %>"
    ProviderName="<%$ ConnectionStrings:NorthwindConnectionString1.ProviderName %>"
    SelectCommand="SELECT [RegionID], [RegionDescription] FROM [Region]"
    >
</asp:SqlDataSource>

'自訂的Sub，用來配合wuc的OnGetData事件
Protected Sub GetData(ByVal sender As Object, ByRef myRegion As MyRegionObj)
    '定義一個wuc1變數，是wucEvent001的類型，並且承接sender
    Dim wuc1 As wucEvent001 = CType(sender, wucEvent001)

    '透過wuc1的parent取得該wuc的Cell
    '再透過FindControl，去找同一層的HiddenFiled
    Dim hidRegionID As HiddenField = CType(wuc1.Parent.FindControl("hidRegionID"), HiddenField)
    Dim hidRegionDescription As HiddenField = CType(wuc1.Parent.FindControl("hidRegionDescription"), HiddenField)

    If Not (hidRegionID Is Nothing) Then
        '如果有取得HiddenField物件
        Dim RegionID As Decimal = CType(hidRegionID.Value, Decimal)
        Dim RegionDescription As String = hidRegionDescription.Value
        '如果傳入的是沒有執行個體(理論上應該是沒有)
        If myRegion Is Nothing Then
            '產生執行個體
            myRegion = New MyRegionObj
        End If
        '將資料設定入物件類別
        myRegion.RegionID = RegionID
        myRegion.RegionDescription = RegionDescription
    End If
End Sub