参考代码
Dim dt1 As DataTable = DataTables("表一")Dim dt2 As DataTable = DataTables("表二")
For Each dr As DataRow In dt1.DataRows dr("数量") = dt2.Compute("Count(名称)", "所属分类 = '" & dr("名称") & "' And 条件 in('条件一','条件二')")Next