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-  Foxtable(狐表)  (http://foxtable.net/bbs/index.asp)
--  专家坐堂  (http://foxtable.net/bbs/list.asp?boardid=2)
----  [求助]filler的机制问题  (http://foxtable.net/bbs/dispbbs.asp?boardid=2&id=120867)
--  作者：chnfo
--  发布时间：2018/6/25 14:52:00
--  [求助]filler的机制问题
\'\'
DataTables("D").DataRows.Clear
Tables("D").AddNew(10000)
For Each r As Row In Tables("D").Rows
r("C") = rand.NextString(12)
r("T") = rand.NextString(12)
r("U") = rand.NextString(12)
r("A") = rand.Next(500)
r("P") = rand.Next(1500)
Next

Dim st As Date = Date.Now
Dim log As String
Dim f As New Filler
f.SourceTable = DataTables("D") \'指定数据来源
f.SourceCols = "C,T,U,A,P" \'指定数据来源列
f.DataTable = DataTables("E") \'指定数据接收表
f.DataCols = "C,T,U,A,P" \'指定数据接收列
f.Fill()
log &=  "FILL耗时: " & (Date.Now - st).TotalSeconds & "秒" & vbcrlf

DataTables("E").DataRows.Clear
Dim st2 As Date = Date.Now
Dim x As new List(of DataRow)
For Each dr As DataRow In DataTables("D").DataRows
    x.Add(dr)
Next

log &=  "得到序列耗时: " & (Date.Now - st2).TotalSeconds & "秒" & vbcrlf

Dim n As Integer = x.Count
log &=  "得到行数耗时耗时: " & (Date.Now - st2).TotalSeconds & "秒" & vbcrlf

DataTables("E").AddNew(n)
log &=  "增加行耗时: " & (Date.Now - st2).TotalSeconds & "秒" & vbcrlf

For i As Integer = 0 To n - 1
    Dim dr As DataRow = DataTables("E").DataRows(i)
    dr("C") = x(i)("C")
    dr("T") = x(i)("T")
    dr("U") = x(i)("U")
    dr("A") = x(i)("A")
    dr("P") = x(i)("P")
Next
log &=  "赋值耗时: " & (Date.Now - st2).TotalSeconds & "秒" & vbcrlf
output.Show(log)

实际测试，如果10000行以内，两种方法相差1秒，但超过万行，达到10万行数据以后，filler需要13秒左右，而后一种方法耗时2倍。
后一种方法还能更快一些吗？
--  作者：有点甜
--  发布时间：2018/6/25 16:04:00
--  

DataTables("D").DataRows.Clear
Tables("D").AddNew(10000)
For Each r As Row In Tables("D").Rows
    r("C") = rand.NextString(12)
    r("T") = rand.NextString(12)
    r("U") = rand.NextString(12)
    r("A") = rand.Next(500)
    r("P") = rand.Next(1500)
Next


Dim st As Date = Date.Now
Dim log As String
Dim f As New Filler
f.SourceTable = DataTables("D") \'指定数据来源
f.SourceCols = "C,T,U,A,P" \'指定数据来源列
f.DataTable = DataTables("E") \'指定数据接收表
f.DataCols = "C,T,U,A,P" \'指定数据接收列
f.Fill()
log &=  "FILL耗时: " & (Date.Now - st).TotalSeconds & "秒" & vbcrlf


DataTables("E").DataRows.Clear
Dim st2 As Date = Date.Now
systemready = False
DataTables("e").StopRedraw
Dim rowArray() As system.data.DataRow = DataTables("d").BaseTable.Select("")
Dim btable As system.data.DataTable =  DataTables("E").basetable
For Each r As system.data.DataRow In rowarray
    Dim dr As system.data.DataRow = btable.newrow
    dr("C") = System.Runtime.CompilerServices.RuntimeHelpers.GetObjectValue(r("C"))
    dr("t") = System.Runtime.CompilerServices.RuntimeHelpers.GetObjectValue(r("t"))
    dr("u") = System.Runtime.CompilerServices.RuntimeHelpers.GetObjectValue(r("u"))
    dr("a") = System.Runtime.CompilerServices.RuntimeHelpers.GetObjectValue(r("a"))
    dr("p") = System.Runtime.CompilerServices.RuntimeHelpers.GetObjectValue(r("p"))
    btable.rows.add(dr)
Next
log &=  "赋值耗时: " & (Date.Now - st2).TotalSeconds & "秒" & vbcrlf
output.Show(log)
DataTables("e").ResumeRedraw
systemready = True
--  作者：chnfo
--  发布时间：2018/6/25 16:27:00
--  
甜兄，什么都不扶，就扶你。比fill还快，可以做成一个通用的方法了。

可以把这个方法整到fill里去呀。