ASP.NET中使用GridView实现分级显示

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
If Not IsPostBack Then
BindGridView()
End If
End Sub

'1.首先找出Customers数据
Public Sub BindGridView()
Dim strSQL As String = "SELECT * FROM Customers"
Dim dtTable As DataTable = GetDataTable(strSQL)
sCount = dtTable.Rows.Count
Me.GridView1.DataSource = dtTable
Me.GridView1.DataBind()
End Sub

'Customers数据绑定时要做的事情
Protected Sub GridView1_RowDataBound(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewRowEventArgs) Handles GridView1.RowDataBound
If e.Row.RowType = DataControlRowType.DataRow Then
Dim HCustomerID As String = CType(e.Row.FindControl("HCustomerID"), HiddenField).Value
Dim TRCustomers As HtmlTableRow = CType(e.Row.FindControl("TRCustomers"), HtmlTableRow)
If HCustomerID.Trim.Length > 0 Then
'鼠标移过时变换css样式。
e.Row.Attributes.Add("onmouseover", "currentcolor=this.className;this.className='MouseOver';")
e.Row.Attributes.Add("onmouseout", "this.className=currentcolor;")
'找出此Customer的所有Orders
Dim strSQL As String = "SELECT * FROM Orders WHERE CustomerID='" & HCustomerID & "'"
Dim dtTable As DataTable = GetDataTable(strSQL)
Dim imgFlag As Image = CType(e.Row.FindControl("imgFlag"), Image)
If dtTable.Rows.Count > 0 Then
Dim GridViewOrders As GridView = CType(e.Row.FindControl("GridViewOrders"), GridView)
GridViewOrders.DataSource = dtTable
GridViewOrders.DataBind()
'设置点击某行时的Javascript
Dim strScript As New StringBuilder
strScript.Append("var obj = document.getElementById('" & TRCustomers.ClientID & "');")
strScript.Append("var objimg = document.getElementById('" & imgFlag.ClientID & "');")
strScript.Append("if (obj.style.display == 'none') {")
strScript.Append("  obj.style.display = '';")
strScript.Append("  objimg.src = 'images/up.gif';")
strScript.Append("}else{")
strScript.Append("  obj.style.display = 'none';")
strScript.Append("  objimg.src = 'images/dn.gif';")
strScript.Append("}")
e.Row.Attributes.Add("onclick", strScript.ToString)
Else
imgFlag.ImageUrl = "~/images/up.gif"
End If
End If
End If
End Sub

Protected Sub doOnRowDataBoundOrders(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewRowEventArgs)
If e.Row.RowType = DataControlRowType.DataRow Then
Dim HOrderID As String = CType(e.Row.FindControl("HOrderID"), HiddenField).Value
Dim TROrders As HtmlTableRow = CType(e.Row.FindControl("TROrders"), HtmlTableRow)
If HOrderID.Trim.Length > 0 Then
'鼠标移过时变换css样式。
e.Row.Attributes.Add("onmouseover", "currentcolor=this.className;this.className='MouseOver';")
e.Row.Attributes.Add("onmouseout", "this.className=currentcolor;")
'找出此Order的所有Order Details
Dim strSQL As String = "SELECT Products.ProductName, [Order Details].UnitPrice, [Order Details].Quantity, [Order Details].UnitPrice * [Order Details].Quantity AS OPrice, [Order Details].Discount, " & _
"([Order Details].UnitPrice * [Order Details].Quantity) * (1.00 - [Order Details].Discount) AS PPrice, Products.QuantityPerUnit " & _
"FROM [Order Details] INNER JOIN Products ON [Order Details].ProductID = Products.ProductID " & _
"WHERE OrderID='" & HOrderID & "'"
Dim dtTable As DataTable = GetDataTable(strSQL)
Dim imgFlag1 As Image = CType(e.Row.FindControl("imgFlag1"), Image)
If dtTable.Rows.Count > 0 Then
Dim GridViewOrderDetails As GridView = CType(e.Row.FindControl("GridViewOrderDetails"), GridView)
GridViewOrderDetails.DataSource = dtTable
GridViewOrderDetails.DataBind()
'设置点击某行时的Javascript
Dim strScript As New StringBuilder
strScript.Append("var obj = document.getElementById('" & TROrders.ClientID & "');")
strScript.Append("var objimg = document.getElementById('" & imgFlag1.ClientID & "');")
strScript.Append("if (obj.style.display == 'none') {")
strScript.Append("  obj.style.display = '';")
strScript.Append("  objimg.src = 'images/up.gif';")
strScript.Append("}else{")
strScript.Append("  obj.style.display = 'none';")
strScript.Append("  objimg.src = 'images/dn.gif';")
strScript.Append("}")
e.Row.Attributes.Add("onclick", strScript.ToString)
End If
End If
End If
End Sub