vb.net 每次点击按钮时，如何在visual basic 1行中从文本文件读取到文本框

how to read from text file to textbox in visual basic 1 line every hit on button

提问by Samer Yousef

I have files type .txt (Text File) and it's have multiple line and i have these pictures

我有文件类型 .txt（文本文件），它有多行，我有这些图片

i want to make program generate fake information

我想让程序生成虚假信息

Mean: when some one hit generate button it's ready from text file and fill textbox in visual basic

意思是：当有人点击生成按钮时，它就可以从文本文件中准备好并在visual basic中填充文本框

every hit(press) on Generate Button make program generate new information from text files (.txt)

每次点击（按下）生成按钮使程序从文本文件（.txt）生成新信息

i tried a lot ways:

我尝试了很多方法：

Code:

代码：

Dim fileReader As String
fileReader = My.Computer.FileSystem.ReadAllText("C:\test.txt")

Code:

代码：

Dim fileReader As String
fileReader = My.Computer.FileSystem.ReadAllText("C:\test.txt", _
   System.Text.Encoding.UTF32)

and this

和这个

Code:

代码：

 Dim oFile as System****.File
Dim oRead as System****.StreamReader
oRead = oFile.OpenText(“C:\test.txt”)

and this

和这个

Code:

代码：

 Dim FILE_NAME As String = "C:\Users\user\Desktop\test.txt"
        Dim objReader As New System.I--O.StreamReader(FILE_NAME)
        TextBox1.Text = objReader.ReadToEnd

Code:

代码：

' Form Load :
Dim text As String = MsgBox("text you want to make the form remember it.")
Or new Sub :
Code:
Private Sub Text
text
Code:
' Button Click :
Text()

Code:

代码：

    Dim path As String = "THE FILE PATH" 'The file path
        Dim reader As New IO.StreamReader(path)
        Dim lineIndex As Integer = 2 ' The index of the line that you want to read
        For i As Integer = 0 To lineIndex - 1
            reader.ReadLine()
        Next
        TextBox1.Text = reader.ReadLine


Public Class Form1

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        TextBox1.Text = ReadLineFromTxt("THE TXT FILE PATH", 0) '0 is the line index
    End Sub

    Public Shared Function ReadLineFromTxt(ByVal path As String, ByVal lineIndex As Integer) As String
        Dim reader As New IO.StreamReader(path)
        For I As Integer = 0 To lineIndex - 1
            reader.ReadLine()
        Next
        Return reader.ReadLine()
    End Function
End Class

These ways take from members in this fourm: http://www.mpgh.net/forum/33-visual-basic-programming/693165-help-how-can-i-generate-text-txt-file-textbox-when-button-click-2.html

这些方法取自本期成员：http://www.mpgh.net/forum/33-visual-basic-programming/693165-help-how-can-i-generate-text-txt-file-textbox-when -button-click-2.html

if are these ways working please tell me how to use it in best way

如果这些方法有效，请告诉我如何以最佳方式使用它

i have Visual studio 2012 and updated 1

我有 Visual Studio 2012 并更新了 1

With all due respect

恕我直言

回答by StingyHyman

Assuming you are reading from a file and displaying lines on the form, you can use these.

假设您正在读取文件并在表单上显示行，您可以使用这些。

If you have a large file (> 10MB), then you can use this pattern... (syntax from memory, please excuse mistype)

如果你有一个大文件（> 10MB），那么你可以使用这个模式......（内存中的语法，请原谅输入错误）

Public Class YourFormNameHere

 Private _CurrentLine as Integer = 0

 Private Sub btnClicked(sender, e) 'or enter pressed - This is YOUR keypress event handler.

  Using Dim sr as New StreamReader(filePath)

   Dim _curIndex as Integer = 0

   While (sr.EndOfFile == false)
    Dim _line as String = sr.ReadLine()         

    If (_curIndex = _CurrentLine)
      txtLineDisplay.Text = _line
      Break
    End If          

    curIndex += 1

   End While
  End Using
 End Sub
End Class

If you have a smaller file, then use this pattern.

如果您的文件较小，请使用此模式。

Public Class YourFormNameHere

 Private _Lines as String()
 Private _CurrentLine as Integer = 0

 Private Sub formLoad(sender, e) 'one-time load event - This is YOUR form load event

   _Lines = File.ReadAllLines(filePath)

 End Sub

 Private Sub btnClicked(sender, e) 'or enter pressed - This is YOUR keypress event handler.

   txtLineDisplay.Text = _Lines[_CurrentLine]
   _CurrentLine += 1

 End Sub
End Class