读取大文本文件VB6中的行数

时间:2012-11-28 05:53:29

标签: vba text vb6

我的文件大小为230MB。我想计算该文件的行数。

我尝试了“ Scripting.FileSystemOblect ”,但内存不足。

请帮助。

感谢。

3 个答案:

答案 0 :(得分:5)

正常的Windows换行符是CRLF,因此您可以计算LF,并在文件的最后一行之后没有一个的情况下为计数加1。

在真正的VB(即VB5,VB6等)中,您可以使用面向字节的字符串操作来加速许多任务。如果我们可以假设文本文件包含ANSI,那么这很快:

Option Explicit

Private Sub Main()
    Const BUFSIZE As Long = 100000
    Dim T0 As Single
    Dim LfAnsi As String
    Dim F As Integer
    Dim FileBytes As Long
    Dim BytesLeft As Long
    Dim Buffer() As Byte
    Dim strBuffer As String
    Dim BufPos As Long
    Dim LineCount As Long

    T0 = Timer()
    LfAnsi = StrConv(vbLf, vbFromUnicode)
    F = FreeFile(0)
    Open "big.txt" For Binary Access Read As #F
    FileBytes = LOF(F)
    ReDim Buffer(BUFSIZE - 1)
    BytesLeft = FileBytes
    Do Until BytesLeft = 0
        If BufPos = 0 Then
            If BytesLeft < BUFSIZE Then ReDim Buffer(BytesLeft - 1)
            Get #F, , Buffer
            strBuffer = Buffer 'Binary copy of bytes.
            BytesLeft = BytesLeft - LenB(strBuffer)
            BufPos = 1
        End If
        Do Until BufPos = 0
            BufPos = InStrB(BufPos, strBuffer, LfAnsi)
            If BufPos > 0 Then
                LineCount = LineCount + 1
                BufPos = BufPos + 1
            End If
        Loop
    Loop
    Close #F
    'Add 1 to LineCount if last line of your files do not
    'have a trailing CrLf.
    MsgBox "Counted " & Format$(LineCount, "#,##0") & " lines in" & vbNewLine _
         & Format$(FileBytes, "#,##0") & " bytes of text." & vbNewLine _
         & Format$(Timer() - T0, "0.0#") & " seconds."
End Sub

鉴于7,000,000行文件293MB,这里只需0.7秒。但请注意,我没有重新启动以确保在运行该测试时文件未被缓存。没有缓存(即重启后),我希望它只需要5倍。

转换为处理Unicode文本文件非常简单。只需用非B等效项替换B函数,确保将BUFSIZE设置为2的倍数,并搜索vbLf而不是ANSI LF字节。

答案 1 :(得分:2)

您可以通过将每一行读入同一个变量来实现。没有必要保存所有行:

dim s as string
dim n as integer

open "filename.txt" for input as 1

n = 0
do while not eof(1)
  line input #1, s
  n = n + 1
  loop

这还没有经过测试,自从我做了任何VB6以来已经有一段时间了,但它应该已经接近了。

答案 2 :(得分:2)

对于一个480m二进制文件,1mil + 0xD(vbcr),这需要大约6秒钟

Dim buff() As Byte
Dim hF As Integer
Dim i As Long, n As Long

hF = FreeFile(0)

Open "c:\windows\Installer\2f91fd.msp" For Binary Access Read As #hF
ReDim buff(LOF(hF) - 1)
Get #hF, , buff()
Close #hF

For i = 0 To UBound(buff)
    If buff(i) = 13 Then n = n + 1
Next

MsgBox n