Dim ta As DataTable = DataTables("表A") Dim tb As DataTable = DataTables("表B") Dim tc As DataTable = DataTables("表C") For Each r As DataRow In ta.DataRows Dim fdr = tb.Find("第一列 = '" & r("第一列") & "'") If fdr Is Nothing Then r("第十列") = "b不存在" Else fdr = tb.Find("第一列 = '" & r("第一列") & "' and 第二列 = '" & r("第二列") & "'") If fdr Is Nothing Then r("第十列") = "第二列不同" Else fdr = tb.Find("第一列 = '" & r("第一列") & "' and 第二列 = '" & r("第二列") & "' and 第三列 = '" & r("第三列") & "'") If fdr Is Nothing Then r("第十列") = "第三列不同" Else r("第十列") = "存在"