怎样写代码，可以修改txt文本中的某一行

[jingyuanlin]

我想把txt文档中的某一行替换成其他内容，应该怎么写呢？

[rainstormmaster]

顺便说一下，northwolves(野性的呼唤) 的代码存在问题，问题是当文件中包含中文时，他的代码会在文件尾部产生多余的空格，这是由：
filetxt = String(FileLen(txtpath), " ")
所造成的，修正如下：
Sub replaceline(txtpath As String, ByVal linenum As Integer, ByVal mystr As String)
Dim filetxt As String, x As Variant, i As Integer
dim j as long
dim buff() as byte
j=filelen(txtpath)
redim buff(j-1)
Open txtpath For Binary As 1
Get #1, , buff
Close 1
filetxt=strconv(buff,vbunicode)
x = Split(filetxt, vbCrLf)

If linenum <= UBound(x) + 1 Then
x(linenum - 1) = mystr
End If
Open txtpath For Binary As 1
Put #1, , Join(x, vbCrLf)
Close 1
Set x = Nothing
MsgBox "ok!"
End Sub

Private Sub Command1_Click()
replaceline "d:\xxxx.txt", 8, "aaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
End Sub

[SoHo_Andy]

这个比较麻烦，如果你的文件不是很大的话建议你读出原文件，解析到那一行，
然后加入你的文本，最后重写文件，给你个文件操作的参考例子，希望给你启发

网友的要求
设有文件a.txt，其中存放了两行数据，数据用逗号分隔，现在要读取第一行的奇数位置的数据写入到另一个文本文件（b.txt）的第一行，类似地，把第二行的奇数位置的数据写入到第二行。
比如：
文件a.txt如下：
1，2，3，4，5
6，7，8，9，10
操作完成后，文件b.txt应为
1,3,5
6,8,10
因为我没有用过vb，希望各位能给出完整一点的代码，谢谢！

解决的代码
Sub 提取奇数位数据(strSourceFile As String, strTargetFile As String)
Dim filenum As Integer
Dim fileContents As String
Dim fileInfo() As String
Dim i As Integer
Dim j As Integer

Dim tmpDemData As String
filenum = FreeFile
Open strSourceFile For Binary As #filenum
fileContents = Space(LOF(filenum))
Get #filenum, , fileContents
Close filenum
fileInfo = Split(fileContents, vbCrLf)
'取出源文件行数，按照回车换行来分隔成数组

filenum = FreeFile
tmpDemData = ""
If Dir(strTargetFile, vbNormal) <> "" Then
Kill strTargetFile
End If
Dim Filestr() As String

Open strTargetFile For Append As #filenum
'循环每一行
For i = 0 To UBound(fileInfo) - 1
Filestr = Split(Trim(fileInfo(i)), ",") '按照逗号分隔每一行的数据
tmpDemData = ""
For j = 0 To UBound(Filestr)
'判断是否为奇数位
If (j Mod 2) = 0 Then
tmpDemData = tmpDemData & Filestr(j)
ElseIf j <> 0 And j <> UBound(Filestr) Then
tmpDemData = tmpDemData & ","
End If
Next
'保存一行如目标文件
Print #filenum, tmpDemData
Next
Close #filenum
MsgBox "完毕"
End Sub

Private Sub Command1_Click()
提取奇数位数据 "d:\aa.txt", "d:\bb.txt"
End Sub

[chao778899]

读出来，写进去，估计没有更好的定位的方法

[northwolves]

rainstormmaster(rainstormmaster) 言之有理，多谢指教。

[kmzs]

up

[northwolves]

Sub replaceline(txtpath As String, ByVal linenum As Integer, ByVal mystr As String)
Dim filetxt As String, x As Variant, i As Integer
filetxt = String(FileLen(txtpath), " ")
Open txtpath For Binary As 1
Get #1, , filetxt
Close 1
x = Split(filetxt, vbCrLf)

If linenum <= UBound(x) + 1 Then
x(linenum - 1) = mystr
End If
Open txtpath For Binary As 1
Put #1, , Join(x, vbCrLf)
Close 1
Set x = Nothing
MsgBox "ok!"
End Sub

Private Sub Command1_Click()
replaceline "d:\xxxx.txt", 8, "aaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
End Sub

[hansong_ll]

一个苯办法，把TXT文件内容一行行读出来，保存到另外一个文件中，找到替换行，替换掉。

[rainstormmaster]

没有好办法，只能全部读出后进行替换，再把替换后的文本写回文件，至于读写文件，可以用open语句，也可以借助FSO对象实现