Как правильно открыть TXT файл для чтения, например чтобы запихнуть в TextBox или просто загрузить в массив строк

Private Sub Command1_Click()
    Dim tick As Long
    Dim str As String
    
    tick = GetTickCount
    
    str = String$(260000000, vbNullChar) ' Работает! Примерно 500 Мб строки данных (по два байта на один символ)
    'str = String$(265000000, vbNullChar) ' Уже не работает! Недостаточно места в строке
    
    Print GetTickCount - tick ' Примерно 180 млск у меня в IDE VB6
End Sub

Option Explicit
Private Declare Function ReadFile Lib "kernel32" (ByVal hFile As Long, ByVal lpBuffer As Long, ByVal nNumberOfBytesToRead As Long, lpNumberOfBytesRead As Long, ByVal lpOverlapped As Any) As Long
Private Declare Function GetFileSize Lib "kernel32" (ByVal hFile As Long, lpFileSizeHigh As Long) As Long
Private Declare Sub PutMem4 Lib "msvbvm60" (ByVal Ptr As Long, ByVal Value As Long)
Private Declare Function SysAllocStringByteLen Lib "oleaut32" (ByVal olestr As Long, ByVal BLen As Long) As Long
Private Declare Function SysAllocStringLen Lib "oleaut32" (ByVal olestr As Long, ByVal BLen As Long) As Long
Private Declare Function MultiByteToWideChar Lib "kernel32" (ByVal CodePage As Long, ByVal dwFlags As Long, ByVal lpMultiByteStr As Long, ByVal cbMultiByte As Long, ByVal lpWideCharStr As Long, ByVal cchWideChar As Long) As Long
Private Declare Function CreateFile Lib "kernel32" Alias "CreateFileW" (ByVal lpFileName As Long, ByVal dwDesiredAccess As Long, ByVal dwShareMode As Long, lpSecurityAttributes As Any, ByVal dwCreationDisposition As Long, ByVal dwFlagsAndAttributes As Long, ByVal hTemplateFile As Long) As Long
Private Declare Function CloseHandle Lib "kernel32" (ByVal hObject As Long) As Long
Private Declare Function GetTickCount Lib "kernel32" () As Long
 
Private Const OPEN_EXISTING As Long = 3
Private Const GENERIC_READ As Long = &H80000000
Private Const CP_UTF8 As Long = 65001
Private Const GENERIC_WRITE As Long = &H40000000
Private Const FILE_SHARE_READ = &H1
Private Const CREATE_ALWAYS = 2
Private Const FILE_ATTRIBUTE_ARCHIVE = &H20
Private Const INVALID_HANDLE_VALUE As Long = -1
 
Public Function ReadFromTextFileUTF8(ByVal FileName As String) As String
    Dim hFile As Long
    Dim stringbuffer As String
    Dim numread As Long
    Dim FileSize As Long
    Dim nOutputCharLen As Long
    Dim lpMultiByteStr As Long
    
    hFile = CreateFile(StrPtr(FileName), GENERIC_READ, FILE_SHARE_READ, ByVal 0&, OPEN_EXISTING, FILE_ATTRIBUTE_ARCHIVE, 0)
    
    If hFile <> INVALID_HANDLE_VALUE Then
        FileSize = GetFileSize(hFile, ByVal 0&) ' Этот метод только до 2Гб
        
        If FileSize > 0 Then
            PutMem4 VarPtr(stringbuffer), SysAllocStringByteLen(0&, FileSize) ' Мгновенно выделить память для строки
            
            If ReadFile(hFile, StrPtr(stringbuffer), FileSize, numread, ByVal 0&) > 0 Then
                If MidB$(stringbuffer, 1, 3) = ChrW(&HBBEF) & ChrB(&HBF) Then ' Если есть запись BOM
                    lpMultiByteStr = StrPtr(stringbuffer) + 3
                Else
                    lpMultiByteStr = StrPtr(stringbuffer)
                End If
                
                nOutputCharLen = MultiByteToWideChar(CP_UTF8, 0&, lpMultiByteStr, FileSize, 0&, 0&)
                If nOutputCharLen > 0 Then
                    PutMem4 VarPtr(ReadFromTextFileUTF8), SysAllocStringLen(0&, nOutputCharLen)
                    MultiByteToWideChar CP_UTF8, 0&, lpMultiByteStr, FileSize, StrPtr(ReadFromTextFileUTF8), nOutputCharLen ' Преобразовать кодировки
                End If
            End If
        End If
        
        CloseHandle hFile
    End If
End Function
 
Public Function ReadFileUTF(ByVal FileName As String) As String
    Dim hFile As Long
    Dim byte_array() As Byte
    Dim numread As Long
    Dim FileSize As Long
    Dim nOutputCharLen As Long
    Dim lpMultiByteStr As Long
    
    hFile = CreateFile(StrPtr(FileName), GENERIC_READ, FILE_SHARE_READ, ByVal 0&, OPEN_EXISTING, FILE_ATTRIBUTE_ARCHIVE, 0)
    
    If hFile <> INVALID_HANDLE_VALUE Then
        FileSize = GetFileSize(hFile, ByVal 0&) ' Этот метод только до 2Гб
        
        If FileSize > 0 Then
            ReDim Preserve byte_array(FileSize - 1)
            
            If ReadFile(hFile, VarPtr(byte_array(0)), FileSize, numread, ByVal 0&) > 0 Then
                If byte_array(0) = &HEF And byte_array(1) = &HBB And byte_array(2) = &HBF Then ' Если есть запись BOM
                    lpMultiByteStr = VarPtr(byte_array(3))
                Else
                    lpMultiByteStr = VarPtr(byte_array(0))
                End If
                
                nOutputCharLen = MultiByteToWideChar(CP_UTF8, 0&, lpMultiByteStr, FileSize, 0&, 0&)
                If nOutputCharLen > 0 Then
                    PutMem4 VarPtr(ReadFileUTF), SysAllocStringLen(0&, nOutputCharLen)
                    
                    If Len(ReadFileUTF) = nOutputCharLen Then ' Если строка была успешно выделена (специально для The Trick) чтобы не придерался ко мне
                        MultiByteToWideChar CP_UTF8, 0&, lpMultiByteStr, FileSize, StrPtr(ReadFileUTF), nOutputCharLen ' Преобразовать кодировки
                    End If
                End If
            End If
        End If
        
        CloseHandle hFile
    End If
End Function
 
' Тестируем загрузку файла размером 180 Мб
Private Sub Command1_Click()
    Dim tick As Long
    Dim str As String
    
    tick = GetTickCount
    
    str = ReadFromTextFileUTF8("C:\Test\Test.txt") ' 843 ml
    
    Me.Caption = GetTickCount - tick
    
    Text1.Text = Mid$(str, 1, 1000)
End Sub
 
Private Sub Command2_Click()
    Dim tick As Long
    Dim str As String
    
    tick = GetTickCount
    
    str = ReadFileUTF("C:\Test\Test.txt") ' 889 ml
    
    Me.Caption = GetTickCount - tick
    
    Text1.Text = Mid$(str, 1, 1000)
End Sub