如下：Dim path As String = ""
Dim fimout As New OpenFileDialog
fimout.Title = "打开文本文件"
fimout.Filter = "文本文件(*.txt)|*.txt"
If fimout.ShowDialog = Windows.Forms.DialogResult.OK Then
path = fimout.FileName
Else
Exit Sub
End If
Dim readtxt As New StreamReader(path, System.Text.Encoding.UTF8)
TextBox1.Text = readtxt.ReadToEnd
readtxt.Close()
但是读取的汉字是乱码，英文的还好，如图，
求指点一二，VB.NET的论坛少，求助不易啊...

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
Dim sw As System.IO.StreamWriter '写入
sw = New System.IO.StreamWriter(Application.StartupPath + "1.txt", False)
sw.WriteLine(TextBox1.Text)
sw.Close()
End Sub Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
Dim sr As System.IO.StreamReader '读取
sr = New System.IO.StreamReader(Application.StartupPath + "1.txt", False)
TextBox1.Text = sr.ReadLine
sr.Close()
End Sub
自己改一下

感谢，不过实际我改了一下试了下，我的还是不能显示汉字，我的代码如下： Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click
Dim sr As System.IO.StreamReader '读取
sr = New System.IO.StreamReader("c:\1.txt")
TextBox1.Text = sr.ReadToEnd
sr.Close()
End Sub
还是向上图所示乱码呢,,,哎，真不知道是怎么回事，，，

Dim sr As System.IO.StreamReader '读取
sr = New System.IO.StreamReader("c:\1.txt", System.Text.Encoding.GetEncoding("GB2312"))
TextBox1.Text = sr.ReadToEnd
sr.Close()
好像是编码问题 你试试看看能不能解决

编码问题 gb2312

回复 楼主 my.computr.filesystem.readalltext() 这个很好用，如果你只是把txt读入textbox的话，用这个很简单，也没乱码。保存的时候是read换成 write

，就是编码问题，谢谢各位，解决后如下：
Private Sub 打开OToolStripButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles 打开OToolStripButton.Click
Dim path As String
Dim readtxt As StreamReader
Dim formout As New OpenFileDialog
formout.Filter = "文本文件 (*.txt)|*.txt|所有文件 (*.*)|*.*"
formout.Title = "测试 打开文本文件"
If formout.ShowDialog = DialogResult.OK Then
path = formout.FileName
Else
Exit Sub
End If
readtxt = New StreamReader(path, System.Text.Encoding.GetEncoding("GB2312"))
TextBox1.Text = readtxt.ReadToEnd
readtxt.Close()
End Sub


FileIO.FileSystem.ReadAllText(文件地址, System.Text.Encoding.Default)

记事本默认使用ansi编码，这种编码在汉子部分和gb那个一样。ansi用getencoding("0")