| 以文本方式查看主题 - Foxtable(狐表) (http://foxtable.com/bbs/index.asp) -- 专家坐堂 (http://foxtable.com/bbs/list.asp?boardid=2) ---- 复制代码的区别 (http://foxtable.com/bbs/dispbbs.asp?boardid=2&id=170860) |
| -- 作者：wangglby -- 发布时间：2021/8/9 22:05:00 -- 复制代码的区别 这段代码把数据从 表A复制到A1 For Each dr1 As DataRow In DataTables("表A").datarows Dim dr2 As DataRow = DataTables("表A1"). sqlfind("编码=\'" & dr1("编码") & "\'") If dr2 Is Nothing Then dr2 = DataTables("表A1").AddNew() For Each dc As DataCol In DataTables("表A").DataCols If DataTables("表A1").DataCols.Contains(dc.name) Then If dc.Expression = "" Then If dr1.IsNull(dc.name) =False Then dr2(dc.Name) = dr1(dc.name) End If End If End If End If Next NEXT 下面 这段代码把选中的数据从表A1复制到A，我发现 第一段效率明显比第二段代码高，请问第二段应该怎么加速？ Dim t As Table = Tables("表A1") Dim a1 As Integer For i As Integer = t.TopPosition To t.BottomPosition Dim dr2 As DataRow = DataTables("表A").AddNew() For Each dc As DataCol In DataTables("表A1").datacols If DataTables("表A").DataCols.Contains(dc.name) Then If dc.Expression = "" Then If t.Rows(i).IsNull(dc.name) =False Then dr2(dc.Name) = t.Rows(i)(dc.name) End If End If End If Next Next |
| -- 作者：有点蓝 -- 发布时间：2021/8/9 22:40:00 -- 看看：http://www.foxtable.com/webhelp/topics/2225.htm 试试 Dim t As Table = Tables("表A1") Dim t1 As Table = Tables("表A") Dim lst As new List(of String) For Each dc As DataCol In DataTables("表A1").datacols If DataTables("表A").DataCols.Contains(dc.name) AndAlso dc.Expression = "" Then lst.add(dc.name) End If Next t1.StopRedraw Dim r,r1 As Row For i As Integer = t.TopPosition To t.BottomPosition r = t1.AddNew() r1 = t.Rows(i) For Each s As String In lst r(s) = r1(s) Next Next t1.ResumeRedraw |