VB文件读写(50分)

如何在VB中实现下列功能：
将A文件添加到B文件末尾。
从B文件中读取N-M字节的内容。

這是我以前寫的程序.是刪除的.希望對你有幫助.
'需要: 引用-- Microsoft Scripting Runtime
'Example: DeleteLine("C:/Myfile.txt", 3)
' 从 Myfile.txt 删除第三行的内容
Dim oFSO As New FileSystemObject
Dim oFSTR As Scripting.TextStream
Dim ret As Long
Dim lCtr As Long
Dim sTemp As String, sLine As String
Dim bLineFound As Boolean
On Error GoTo ErrorHandler
If oFSO.FileExists(fName) Then
Set oFSTR = oFSO.OpenTextFile(fName)
lCtr = 1
Do While Not oFSTR.AtEndOfStream
sLine = oFSTR.ReadLine
If lCtr <> LineNumber Then
sTemp = sTemp & sLine & vbCrLf
Else
bLineFound = True
End If
lCtr = lCtr + 1
Loop
oFSTR.Close
Set oFSTR = oFSO.CreateTextFile(fName, True)
oFSTR.Write sTemp
DeleteLine = bLineFound
End If
ErrorHandler:
On Error Resume Next
oFSTR.Close
Set oFSTR = Nothing
Set oFSO = Nothing
End Function
Private Sub Command1_Click()
Call DeleteLine("C:/aa.txt", 2)
'通用
End Sub

接受答案了.