VB文件追加和覆盖

Ark.xu 2011-06-17

展开全文

Private Sub ReadTxt(ByVal PathName As String)
    
    Dim IntPrompt As Integer
    Dim IntFileNo As Integer
    Dim StrTxt As String
    
    On Error GoTo ErrOccured
    'Input和Output用于文本文件，而Binary和Random用于二进制文件(如：doc就是二进制文件)
    IntFileNo = FreeFile() '文件句柄
    'Open PathName For Input As IntFileNo  '较简单的写法
    Open PathName For Input Access Read Lock Read As IntFileNo
    IntPrompt = MsgBox("只读一行还是全文读取？" & Chr(13) & Chr(10) & "点击“是”只读一行，点击“否”全文读取", vbInformation + vbYesNoCancel, "读取")
    If IntPrompt = vbYes Then
        '先清空文本
        Txt.Text = ""
'        'Input语句在遇到第一个逗号或者空格则停止。通常用 Input # 从文件读出 Write # 写入的数据。
'        Input #IntFileNo, StrTxt
        'Line Input语句在遇到第一个回车(Chr(13))或回车换行（Chr(13)+Chr(10)）时停止
        Line Input #IntFileNo, StrTxt
        Txt.Text = StrTxt
    ElseIf IntPrompt = vbNo Then
        '先清空文本
        Txt.Text = ""
        Do While Not EOF(IntFileNo)
            Line Input #IntFileNo, StrTxt
            Txt.Text = Txt.Text & StrTxt & Chr(13) & Chr(10)
        Loop
    Else
        MsgBox "读取动作被取消", vbInformation + vbMsgBoxRtlReading, "Cancel"
        Exit Sub
    End If
    '这里的判断其实是多余的，如果IntFileNo作为窗体级的变量则可以加此判断
    If IntFileNo <> 0 Then
        Close IntFileNo
    End If
    Exit Sub
ErrOccured:
    '带有搞笑性质的MsgBox
    IntPrompt = MsgBox("分特！没读成功啊！重读吗？", vbMsgBoxRtlReading + vbCritical + vbYesNo, "真笨")
    If IntPrompt = vbYes Then Resume
End Sub

Private Sub WriteTxt(ByVal PathName As String)
    
    Dim IntPrompt As Integer
    Dim StrTxt As String
    Dim myVariant As Variant
    
    'On Error GoTo ErrOccured
    StrTxt = Txt.Text
    IntPrompt = MsgBox("覆盖文件还是追加？" & Chr(13) & Chr(10) & "点击“是”覆盖，点击“否”追加", vbYesNoCancel + vbQuestion, "写入")
    Select Case IntPrompt
    Case vbYes
        '覆盖
        Open PathName For Output Lock Write As #1
        'Print和Write的区别在于：如果今后想用 Input # 语句读出文件的数据，就要用 Write # 语句而不用 Print # 语句将数据写入文件
        '通常用 Print # 将 Line Input # 语句读出的数据从文件中写出来。
        Print #1, StrTxt
        '与 Print # 语句不同，当要将数据写入文件时，Write # 语句会在项目和用来标记字符串的引号之间插入逗号。没有必要在列表中键入明确的分界符。
        '通常用 Write # 将 Input # 语句读出的数据写入文件。
'        Write #1, StrTxt
        Close #1
    Case vbNo
        '追加
        Open PathName For Append Lock Write As #1
        Print #1, StrTxt
'        Write #1, StrTxt
        Close #1
    Case Else
        MsgBox "写入动作被取消", vbInformation + vbMsgBoxRtlReading, "Abort"
        Exit Sub
    End Select
    MsgBox "写入成功！"
    '打开文件观察结果(暂时未写)
    
    Exit Sub
ErrOccured:
    IntPrompt = MsgBox("分特！没写成功啊！重写吗？", vbMsgBoxRtlReading + vbExclamation + vbYesNo, "真笨")
    If IntPrompt = vbYes Then Resume
End Sub