指定水平和垂直移动

Question

我希望能够在管道("|")分隔的文本文件中移动，控制我读取的行和列。

我以前在MS Access VBA中已经实现了这一点，目前正在 VB.NET 开始，但正在努力完成此操作。

在 Access 中，VBA 允许我以记录集 (Dim rs As DAO.Recordset) 的形式链接到文本文件，预定义为分隔并在行(rs.MoveNext或rs.MovePrevious)之间移动，同时选择我需要的字段/列(rs!Field1)。

VB.NET 中是否有等效项？ 到目前为止，我只能从MSDN中找到以下内容，但不知道如何操作它：

Using MyReader As New Microsoft.VisualBasic.FileIO.TextFieldParser(FName)
MyReader.TextFieldType = FileIO.FieldType.Delimited
MyReader.SetDelimiters("|")
Dim currentrow As String()
While Not MyReader.EndOfData
currentrow = MyReader.ReadFields()
Dim currentfield As String
For Each currentfield In currentrow
MsgBox(currentfield)
Next
End While
End Using

我希望能够将某些字段存储到要写入的变量中。稍后的 CSV 文件。

Answer 1

对于任何可能有帮助的人，我设法在以下两个网站的帮助下解决了这个问题：

循环访问目录中的文件

分隔数据

使用这些，我创建了以下按钮单击子和随附的功能：

Private Sub Button_Run_Click(sender As Object, e As EventArgs) Handles Button_Run.Click
' Make a reference to a directory
Dim strDir As String = ("C:")
Dim Dir As New System.IO.DirectoryInfo(strDir)
' Get a reference to each file in that directory
Dim fiArr As System.IO.FileInfo() = Dir.GetFiles()
Dim fri As System.IO.FileInfo
'For each file call the formatter to write to a text file
'Then delete each file after writing it
For Each fri In fiArr
Call Formatter(strDir & fri.Name)
My.Computer.FileSystem.DeleteFile(strDir & fri.Name)
Next fri
End Sub

然后，我用分隔符拆分每一行，其中每个字段都可以获得(使用定义的values(0)变量)和修改(使用它的索引)。控制线条就像使用创建新变量一样简单，或者通过更改整数i修改现有变量。例如：

Dim Nvalues() As String = lines(i + 1).Split("|")

使用它，我创建了以下函数：

Public Sub Formatter(ByVal FName As String)
'Standard start defining stream reader to loop
'through and pull data from text files
'FName is provided from the form button sub
Dim StrReader As New System.IO.StreamReader(FName)
Dim text As String = StrReader.ReadToEnd
StrReader.Close()
Dim lines() As String = text.Split(vbLf)
'Define all variables that may need to be stored before writing
Dim x1, x2, x3, x4, x5, x6, x7, x8, x9, x0 As String
'Define where the data will be written to (line by line)
Dim FPath As String = "C:Sample.txt"
If Not System.IO.File.Exists(FPath) Then
System.IO.File.Create(FPath).Dispose()
End If
Dim objwriter As System.IO.StreamWriter
'Set loop to go through all data from beginning to end using i as line index
Dim i As Double
For i = 0 To lines.Length - 1
'Split each line by pipes (|) allowing "values" to be indexed to pull by column
Dim values() As String = lines(i).Split("|")
'Set 1st column in row as switch item
Select Case values(0)
'If 1st column in row is 001, store required data in variables
'specified using the index of the value to give accurate column
Case "001"
x1 = values(1)
x2 = values(2)
x3 = values(3)
x3 = values(4)
'Repeat same as 001 but for 002
Case "002"
x4 = values(1)
x5 = values(2)
'Repeat same as 001 but for 003
Case "003"
x6 = values(1)
x7 = values(2)
'Write to file including fields 1 & 3 from 004 group
Case "004"
objwriter = System.IO.File.AppendText(FPath)
objwriter.WriteLine(x1 & "," & x2 & "," & x3 & "," & x4 _
& "," & x5 & "," & x6 & "," & x7 & "," _
& Nvalues(1) & "," & Nvalues(2))
objwriter.Close()
Case Else
End Select
Application.DoEvents()
Next
End Sub