Stringbuilder kan ikke læse resterende linier

Note: problemet opstår selvfølgelig ikke hvis man er i debugging mode i Visual Studio

Hi
jeg ku ikke se din API kald og variablerne, derfor kunne ikke genskabe problemet. Men se om nedenstående virker.

    Private Const EM_GETLINECOUNT As Integer = &HBA
    Private Const EM_GETLINE As Integer = &HC4
    Private Const EM_LINELENGTH As Integer = &HC1
    Private Const EM_LINEINDEX As Integer = &HBB

    Private Declare Function SendMessageINT Lib "user32.dll" _
        Alias "SendMessageA" (ByVal hWnd As IntPtr, _
        ByVal wMsg As Integer, ByVal wParam As Integer, _
        ByVal lParam As IntPtr) As Integer

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim LineCount As Integer = SendMessageINT(TextBox1.Handle, EM_GETLINECOUNT, 0, IntPtr.Zero)
        Dim counter As Integer = 0
        Dim LineIndex As Integer = 0
        Dim lineLength As Integer
        Dim curLine As String = ""
        Dim stringPTR As IntPtr

        For counter = 0 To LineCount - 1
           
            LineIndex = SendMessageINT(TextBox1.Handle, EM_LINEINDEX, counter, IntPtr.Zero)
           
            lineLength = SendMessageINT(TextBox1.Handle, EM_LINELENGTH, LineIndex, IntPtr.Zero)

            'Buffer
            curLine = New String("0"c, lineLength + 1)

            'Pointer til buffer
            stringPTR = System.Runtime.InteropServices.Marshal.StringToHGlobalAnsi(curLine)
           
            SendMessageINT(TextBox1.Handle, EM_GETLINE, counter, stringPTR)
            'Læser linien
            curLine = System.Runtime.InteropServices.Marshal.PtrToStringAnsi(stringPTR)
            curLine = curLine.Substring(0, lineLength)
 
            TextBox2.Text = TextBox2.Text + curLine + vbCrLf

            'Ryd op
            System.Runtime.InteropServices.Marshal.FreeHGlobal(stringPTR)
            stringPTR = IntPtr.Zero
        Next

    End Sub

...