Dim crs As New List(Of DataRow)
For Each dr As DataRow In DataTables("包厢号表").DataRows
Dim cr As DataRow = DataTables("前台订房表").Find("包厢号='" & dr("房号") & "'")
If cr Is Nothing Then
crs.Add(dr)
End If
Next
Dim st As Date = Date.Now
'要测试耗时的代码
Systemready = False
DataTables("前台订房表").StopRedraw
For Each dr As DataRow In crs
Dim vr As DataRow = DataTables("前台订房表").AddNew
vr("SysId") = Functions.Execute("数据表编号", "前台订房表")
vr("营业日期") = yyrq
vr("包厢号") = dr("房号")
vr("状态") = "空房"
Next
DataTables("前台订房表").ResumeRedraw
DataTables("前台订房表").Save
Systemready = True
MessageBox.Show("耗时: " & (Date.Now - st).TotalSeconds & "秒")
蓝色代码增加45行数据,就要12秒多,有啥办法可以优化吗?
测试一下：
1、去掉保存的代码，看看要多长时间
2、直接给id取一个固定值（比如vr("SysId") = 1），测试要多长时间
蓝版,查了下,是
Functions.Execute("数据表编号", "前台订房表")
这个函数的问题,函数代码在下面,这个要怎么优化呢?
Dim bm As String = args(0)
Dim cmd As New SQLCommand
cmd.C
cmd.CommandText = "s elect * from {编码表}"
Dim dt As DataTable = cmd.ExecuteReader(True)
Dim dr As DataRow = dt.Find("表名 ='" & bm & "'")
If dr IsNot Nothing Then
If Date.Today > dr("日期") Then '如果今天的日子大于存在表格里的日期
dr("日期") = Date.Today
dr("序号") = 0
Else
dr("序号") = dr("序号") + 1 '如果和今天的日子一样，则序号+1
End If
Dim s As String = dr("前缀名") + Format(Date.Today, "yyMMdd") + Format(dr("序号"), "0000")
dr.Save
Return(s)
End If
方法1、另外建一个函数，一次性返回多个编号，大概
Dim bm As String = args(0)
Dim 行数 As integer = args(1)
Dim cmd As New SQLCommand
cmd.C
cmd.CommandText = "s elect * from {编码表}"
Dim dt As DataTable = cmd.ExecuteReader(True)
Dim dr As DataRow = dt.Find("表名 ='" & bm & "'")
If dr IsNot Nothing Then
If Date.Today > dr("日期") Then '如果今天的日子大于存在表格里的日期
dr("日期") = Date.Today
dr("序号") = 行数
Else
dr("序号") = dr("序号") + 行数 '如果和今天的日子一样，则序号+1
End If
dr.Save
Return(dr("序号") + 1)
End If
-----------
……
DataTables("前台订房表").StopRedraw
dim 编号索引 as integer = Functions.Execute("数据表编号2", "前台订房表",crs.count)
For Each dr As DataRow In crs
Dim vr As DataRow = DataTables("前台订房表").AddNew
vr("SysId") = dr("前缀名") + Format(Date.Today, "yyMMdd") + Format(编号索引, "0000")
编号索引 = 编号索引 + 1
vr("营业日期") = yyrq
……
方法1、2个表如果在同一个数据库，建议使用存储过程处理