VB.NET linq 如何left join （帶測試代碼）

[JirlangLianHongCh]

linq left join 測試代碼 有數據EXCEL表 謝謝大神幫忙解決下：
http://t-1.tuzhan.com/79de13608b2d/p-2/f1927409c2a43ebf/2014/01/18/17/8e2648419ca744069b581e83d6646ce0.jpg

2個datatable結果集合併（LEFT JOIN）
excel2003測試表
SUVZHG：
http://pan.baidu.com/s/1i39Nkln
TOPRC：
http://pan.baidu.com/s/1gd417Xp

Function SUVZHG() As DataTable
        Dim fileName As String
        Dim kk As New OpenFileDialog()
        kk.FileName = "SUVZHG"
        kk.Filter = "Excle恅璃(*.xls)|*.xls"
        If kk.ShowDialog() = DialogResult.OK Then
            fileName = kk.FileName
            Dim strConn As String = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source='" & fileName & "';Extended Properties=Excel 8.0;"
            Dim dr As New DataTable
            Dim da As New OleDbDataAdapter("SELECT * FROM [Sheet1$]", strConn)
            Try
                da.Fill(dr)
                SUVZHG = dr
            Catch ex As Exception
                MsgBox(ex.Message.ToString)
            End Try
        End If
    End Function
    Function TOPRC() As DataTable
        Dim fileName As String
        Dim kk As New OpenFileDialog()
        kk.FileName = "TOPRC"
        kk.Filter = "Excle恅璃(*.xls)|*.xls"
        If kk.ShowDialog() = DialogResult.OK Then
            fileName = kk.FileName
            Dim strConn As String = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source='" & fileName & "';Extended Properties=Excel 8.0;"
            Dim dr As New DataTable
            Dim da As New OleDbDataAdapter("SELECT * FROM [Sheet1$]", strConn)
            Try
                da.Fill(dr)
                TOPRC = dr
            Catch ex As Exception
                MsgBox(ex.Message.ToString)
            End Try
        End If
    End Function
    Private Sub Button1_Click_1(sender As Object, e As EventArgs) Handles Button1.Click
        Dim q = From emp In TOPRC() Group Join emc In SUVZHG() On emp("JSX") Equals emc("JSX") Into DataGroup = Group
       From row In DataGroup.DefaultIfEmpty()
Select emp, Order = row
        DG1.DataSource = q.CopyToDataTable
    End Sub

[q107770540]

给你个例子，你参考一下，我想你可以写的出来：

Public Sub Linq105()
    Dim categories() = {"Beverages", "Condiments", "Vegetables", "Dairy Products", "Seafood"}

    Dim productList = GetProductList()

    Dim query = From c In categories _
                Group Join p In productList On c Equals p.Category Into Group _
                From p In Group.DefaultIfEmpty() _
                Select Category = c, ProductName = If(p Is Nothing, "(No products)", p.ProductName)

    For Each v In query
        Console.WriteLine(v.ProductName + ": " + v.Category)
    Next
End Sub

http://msdn.microsoft.com/zh-cn/vstudio/bb737909#lojoin

[七安谦]

非常感谢，找了好久

[JirlangLianHongCh]

哈哈感謝版主q107770540的解惑！