如何在VB中的数据表中添加基于现有列的新列？

Question

我试图建立一个代码来处理从指纹机到报告文本文件。

文本文件输入例如，

001;0000000000200004;01-07-2016;15:31;01;01

用分号分隔符，

machinecode;personid;dateDD-MM-YYYY;timeHH:MM;jobid;unused

这是我最后一次成功的代码

Imports System.IO 
Imports System.Windows.Forms 

Public Class Form1 

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click 
    Dim lines = IO.File.ReadAllLines("C:\Users\Adventa\Documents\Visual Studio 2010\Projects\AbsensiALU\AbsensiALU\Absen.txt") 
    Dim tblabsen = New DataTable 
    Dim colCount = lines.First.Split(";"c).Length 

    For i As Int32 = 1 To colCount 
     'Dim header As String 
     tblabsen.Columns.Add(New DataColumn("Column_" & i, GetType(String))) 
    Next 
    For Each line In lines 
     Dim objFields = From field In line.Split(";"c) 

     Dim newRow = tblabsen.Rows.Add() 


     newRow.ItemArray = objFields.ToArray() 

    Next 
    Dim table1 As New DataTable 
    table1 = tblabsen.Copy() 

    table1.Columns(0).ColumnName = "No. Mesin" 
    table1.Columns(1).ColumnName = "NIK" 
    table1.Columns(2).ColumnName = "Tanggal" 
    table1.Columns(3).ColumnName = "Jam" 
    table1.Columns(4).ColumnName = "Keterangan" 

    DataGridView1.DataSource = table1 
    DataGridView1.AutoResizeColumn(0) 
    DataGridView1.AutoResizeColumn(1) 
    DataGridView1.AutoResizeColumn(2) 
    DataGridView1.AutoResizeColumn(3) 
    DataGridView1.AutoResizeColumn(4) 

    DataGridView1.Columns(5).Visible = False 


    Dim rowData As String = "" 

    'dt is the name of the data table 
    For Each row As DataRow In table1.Rows 
     For Each column As DataColumn In table1.Columns 
      rowData = rowData & column.ColumnName & "=" & row(column) & " " 
     Next 
     rowData = rowData & vbNewLine & vbNewLine 
    Next 



End Sub 



Private Sub DataGridView1_CellContentClick_1(ByVal sender As System.Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles DataGridView1.CellContentClick 


End Sub 

End Class 

现在我想添加一个柱成它，基于table1.columns（4）配有可能是一个IF/CASE操作者，因此，例如在新的列将是这样

Dim kete As String 
Select Case tblabsen.Columns(4).GetType.ToString() 
      Case "00" 
       kete = "Masuk" 
      Case "01" 
       kete = "Pergi" 
      Case "02" 
       kete = "Kembali" 
      Case "03" 
       kete = "Pulang" 
      Case Else 
       kete = "Error" 
     End Select 

假定“凯泰”可被写入到新列。

在此先感谢。

Answer 1

你必须创建自己的DataTable，所以你需要额外添加一列第一

For i As Int32 = 1 To colCount + 1 
    'Dim header As String 
    tblabsen.Columns.Add(New DataColumn("Column_" & i, GetType(String))) 
Next 

之后，你需要在ForEach

For Each line In lines 
    Dim objFields = line.Split(";"c).ToList() 
    Dim newRow = tblabsen.Rows.Add() 

    Dim kete As String 
    Select Case objField(4).GetType.ToString() 
     Case "00" 
      kete = "Masuk" 
     Case "01" 
      kete = "Pergi" 
     Case "02" 
      kete = "Kembali" 
     Case "03" 
      kete = "Pulang" 
     Case Else 
      kete = "Error" 
    End Select 
    objFields.Add(kete) 

    newRow.ItemArray = objFields.ToArray() 
Next 

分配你的价值，你也需要处理这个额外的列在你的代码的其余部分（即调整大小，列名称）