vb.net 使用文件名过滤器查找文件

Find files with filename filter

提问by Garry

I am using VB.net VS2012 and am having trouble with getting a list of files with a filter.

我正在使用 VB.net VS2012 并且在获取带有过滤器的文件列表时遇到问题。

Here is my code:

这是我的代码：

Public Function SearchAndAddToListWithFilter(ByVal path As String, ByVal Recursive As Boolean, arrayListOfFilters As ArrayList, ByRef listOfFiles As List(Of FileInfo))
    If Not Directory.Exists(path) Then Exit Function

    Dim initDirInfo As New DirectoryInfo(path)

    For Each oFileInfo In initDirInfo.GetFiles
        Application.DoEvents()
        For x = 0 To arrayListOfFilters.Count - 1
            If (oFileInfo.Name Like arrayListOfFilters(x)) Then
                listOfFiles.Add(oFileInfo)
            End If
        Next
    Next

    If Recursive Then
        For Each oDirInfo In initDirInfo.GetDirectories
            SearchAndAddToListWithFilter(oDirInfo.FullName, True, arrayListOfFilters, listOfFiles)
        Next
    End If

End Function

And here is an example of how to use it:

这是如何使用它的示例：

    Dim stringFilterList As String = "*.mp3, *.docx, *.mp3, *.txt"
    Dim arrayListOfFilenameFilters As New ArrayList(stringFilterList.Split(","))
    Dim stringFolderPath As String = "C:\temp\folder\"
    Dim booleanSearchSubFolders As Boolean = True

    Dim listOfFilesFoundViaSearch As New List(Of FileInfo)
    SearchAndAddToListWithFilter(stringFolderPath, booleanSearchSubFolders, arrayListOfFilenameFilters, listOfFilesFoundViaSearch)

    For x = 0 To listOfFilesFoundViaSearch.Count - 1
        MsgBox(listOfFilesFoundViaSearch(x).FullName)
    Next

For some reason, the code only adds the files to the list that satisy the first condition in the list of filters.

出于某种原因，该代码仅将满足过滤器列表中第一个条件的文件添加到列表中。

Can I please have some help to get this code working?

我可以请一些帮助以使此代码正常工作吗？

Thank you.

谢谢你。

回答by Steve

Functions return values, and passing a value ByRef is NOT the way to do it.

函数返回值，通过 ByRef 传递值不是这样做的方法。

The following function will work:

以下功能将起作用：

Private Function SearchAndAddToListWithFilter(ByVal path As String, ByVal filters As String(), ByVal searchSubFolders As Boolean) As List(Of IO.FileInfo)
    If Not IO.Directory.Exists(path) Then
        Throw New Exception("Path not found")
    End If

    Dim searchOptions As IO.SearchOption
    If searchSubFolders Then
        searchOptions = IO.SearchOption.AllDirectories
    Else
        searchOptions = IO.SearchOption.TopDirectoryOnly
    End If

    Return filters.SelectMany(Function(filter) New IO.DirectoryInfo(path).GetFiles(filter, searchOptions)).ToList
End Function

and to use this function:

并使用此功能：

Dim filters As String() = {"*.mp3", "*.docx", "*.bmp", "*.txt"}
Dim path As String = "C:\temp\folder\"

Dim foundFiles As List(Of IO.FileInfo) = SearchAndAddToListWithFilter(path, filters, True)

回答by DrMarbuse

The solution provided by @Steve really shows the .NET way of doing the task. However I used a recursive solution with possible definitions of maximum depth and/or duration. For completeness of this topic, I want to post the code:

@Steve 提供的解决方案真正展示了 .NET 完成任务的方式。但是，我使用了递归解决方案，其中可能定义了最大深度和/或持续时间。为了本主题的完整性，我想发布代码：

''' <summary>
''' Search files in directory and subdirectories 
''' </summary>
''' <param name="searchDir">Start Directory</param>
''' <param name="searchPattern">Search Pattern</param>
''' <param name="maxDepth">maximum depth; 0 for unlimited depth</param>
''' <param name="maxDurationMS">maximum duration; 0 for unlimited duration</param>
''' <returns>a list of filenames including the path</returns>
''' <remarks>
''' recursive use of   Sub dirS
''' 
''' [email protected]
''' </remarks>
Public Shared Function dirRecursively(searchDir As String, searchPattern As String, _
                                    Optional maxDepth As Integer = 0, _
                                    Optional maxDurationMS As Long = 0) As List(Of String)
    Dim fileList As New List(Of String)
    Dim depth As Integer = 0
    Dim sw As New Stopwatch

    dirS(searchDir, searchPattern, maxDepth, maxDurationMS, fileList, depth, sw)

    Return fileList

End Function

''' <summary>
''' Recursive file search
''' </summary>
''' <param name="searchDir">Start Directory</param>
''' <param name="searchPattern">Search Pattern</param>
''' <param name="maxDepth">maximum depth; 0 for unlimited depth</param>
''' <param name="maxDurationMS">maximum duration; 0 for unlimited duration</param>
''' <param name="fileList">Filelist to append to</param>
''' <param name="depth">current depth</param>
''' <param name="sw">stopwatch</param>
''' <param name="quit">boolean value to quit early (at given depth or duration)</param>
''' <remarks>
''' [email protected]
''' </remarks>
Private Shared Sub dirS(searchDir As String, searchPattern As String, _
                            Optional maxDepth As Integer = 0, _
                            Optional maxDurationMS As Long = 0, _
                            Optional ByRef fileList As List(Of String) = Nothing, _
                            Optional ByRef depth As Integer = 0, _
                            Optional ByRef sw As Stopwatch = Nothing, _
                            Optional ByRef quit As Boolean = False)

    If maxDurationMS > 0 Then
        If depth = 0 Then
            sw = New Stopwatch
            sw.Start()
        Else
            If sw.ElapsedMilliseconds > maxDurationMS Then
                quit = True
                Exit Sub
            End If
        End If
    End If

    If maxDepth > 0 Then
        If depth > maxDepth Then
            quit = True
            Exit Sub
        End If
    End If

    ' check if directory exists
    If Not Directory.Exists(searchDir) Then
        Exit Sub
    End If

    ' find files
    For Each myFile As String In Directory.GetFiles(searchDir, searchPattern)
        fileList.Add(myFile)
    Next

    ' recursively scan subdirectories 
    For Each myDir In Directory.GetDirectories(searchDir)
        depth += 1
        dirS(myDir, searchPattern, maxDepth, maxDurationMS, fileList, depth, sw, quit)
        If quit Then Exit For
        depth -= 1
    Next

End Sub

回答by Rodel Calaguan

ListView1.Items.Clear()

ListView1.Items.Clear()

        For Each files As String In System.IO.Directory.GetFiles(cmb_Drives.SelectedItem.ToString, txtSearch.Text)

            Dim ico As Icon = System.Drawing.Icon.ExtractAssociatedIcon(files)
            ImageList1.Images.Add(ico)

            Dim list As ListViewItem = New ListViewItem(My.Computer.FileSystem.GetFileInfo(files).FullName, ImageList1.Images.Count - 1)
            ListView1.Items.Add(list)

        Next