主题：请教关于销售后库存的问题

Dim dr As DataRow

Dim cmd1 As New SQLCommand

Dim dt1 As DataTable

cmd1.CommandText = "SELECT * From {销售表}"

dt1=cmd1.ExecuteReader(True)

Dim cmd As New SQLCommand

Dim dt As DataTable

cmd.CommandText = "SELECT * From {商品入库}"

dt = cmd.ExecuteReader(True)

Dim Arys As List(Of String())

Arys = dt1.GetValues("产品名称|数量")

For Each Ary As String() In Arys

    dr= dt.Find("产品名称 ='" & Ary(0) & "'")

    If dr IsNot Nothing Then

        dr("可用库存")=dt.Compute("Sum(入库数量)","产品名称='" & Ary(0) & "'")-dt1.Compute("Sum(数量)","产品名称='" & Ary(0) & "'")

    End If

    dt.Save

    dr= DataTables("商品入库").Find("产品名称 ='" & Ary(0) & "'")

    If dr IsNot Nothing Then

        dr.load

    End If

Next