Question

i am using following code to search my computer for files with certian extensions. I currenty searching for .eml files. This code lists all files found.
I need to enter 10 most current files’ path to my list box. How can I do it? Thanks

Dim DriveLetter As String = "c:\" '"
Dim Ext As String = ".eml"

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
    Me.SearchPath(DriveLetter)
End Sub

Sub SearchPath(ByVal Path As String)
    Dim DirParent As New IO.DirectoryInfo(Path)
    ''# Me.AddResults("Searching: " & DirParent.FullName)
    Dim ListFiles() As IO.FileInfo

    Try
        ListFiles = DirParent.GetFiles("*" & Ext)
        For Each SingleFile In ListFiles
            Me.AddResults("Found: " & SingleFile.FullName)
            Application.DoEvents()
        Next

    Catch ex As Exception
        ''# Me.AddResults("GET FILES ERROR: " & ex.Message)

    End Try

    Try
        Dim DirChildren() As IO.DirectoryInfo = DirParent.GetDirectories

        For Each DirEnum In DirChildren
            SearchPath(DirEnum.FullName)
        Next

    Catch ex As Exception
        ''# Me.AddResults("GET DIRS ERROR: " & ex.Message)

    End Try
End Sub

Sub AddResults(ByVal ResultString As String)
    lstFiles.Items.Add(ResultString)
    Application.DoEvents()
End Sub

Answer 1

Instead of adding the found files to list box directory add the found FileInfo to a list first. When all the files have been found use a linq query to find the 10 most recent files and add that to the list.

Imports System
Imports System.Collections.Generic
Imports System.IO
Imports System.Linq

Private Sub Button1_Click(ByVal sender As System.Object,
                          ByVal e As System.EventArgs
) Handles button1.Click

    ' Note C:\\ is required to stackoverflow.com formatting '
    Dim foundFiles = SearchPath("C:\\", ".eml")
    Dim recentFiles = From file In foundFiles
                      Order By File.LastWriteTime Descending
                      Take 10

    lstFiles.Items.Clear()

    For Each file In recentFiles

        lstFiles.Items.Add(file.FullName)

    Next

End Sub

Function SearchPath(ByVal path As String,
                    ByVal ext As String
) As List(Of FileInfo)

    Dim dirParent = New IO.DirectoryInfo(path)
    Dim foundFiles = New List(Of FileInfo)

    foundFiles.AddRange(dirParent.GetFiles("*" & ext))

    For Each directory In dirParent.GetDirectories()

        Try

            foundFiles.AddRange(SearchPath(directory.FullName, ext))

        Catch ex As System.UnauthorizedAccessException

            ' Ignore these exceptions. '

        End Try

    Next

    Return foundFiles

End Function