我想建立自己的平面文件数据库.以下是我访问平面文件数据库的方法
- Dim fs As New System.IO.FileStream("C:\MyDb.txt",IO.FileMode.Open,IO.FileAccess.Read,IO.FileShare.Read)
- Dim sr As New System.IO.StreamReader(fs)
在处理文件时,.Net是否限制使用System.IO.FileShare.Read,System.IO.FileShare.Write和System.IO.FileShare.ReadWrite?
我的意思是.Net能够支持成千上万的用户使用文件流和流读取器对象与System.IO.FileShare.Read同时访问单个文件?
解决方法
我不知道.NET / windows强加的确切限制,所以我为你创建了一个真正的测试.我运行了以下测试代码几分钟,我发现最多635908次使用system.io.fileshare,它仍然可用,即你仍然可以读取平面数据库文件的内容.
这是代码(它是一个winform应用程序,.Net 4):
- Public Class Form1
- Private Sub Button1_Click(sender As System.Object,e As System.EventArgs) Handles Button1.Click
- Dim filepath As String = "c:\database.txt"
- Dim filestream As System.IO.FileStream
- Dim count As Int32
- For count = 0 To System.Int32.MaxValue
- filestream = New System.IO.FileStream(filepath,System.IO.FileMode.Open,System.IO.FileAccess.Read,System.IO.FileShare.Read)
- AppendLog(count,filestream.ReadByte)
- Next
- End Sub
- Private LogFilepath As String = "C:\LogInfo.txt"
- Private Enter As String = Chr(13) & Chr(10)
- Private Space As String = " "
- Private Sub AppendLog(ByVal Sequence As Int32,ByVal info As Byte)
- System.IO.File.AppendAllText(LogFilepath,Enter & Sequence & Space & CStr(info))
- End Sub
- End Class