So I have two ListBoxes. Listbox1 gathers files from a directory and I have an add button to add selected files from Listbox1 over to Listbox2.
Is there a way to manually sort these items? Maybe with an up down buttons?
The reason I'd like to sort/reorder is I'll have a process that will run those selected files and each file will have to produce another file unique to the filename.
A quick example would be process FILE1.txt and produce FILE1.pdf, etc.
Is there an easier way to accomplish the sort/reorder?
UPDATE
Here is currently how I'm populating my listbox1, before adding anything to listbox2, which is the ListBox I'd like to have sorted so way or another.
Dim directoryInfo As _
New System.IO.DirectoryInfo(FolderBrowserDialog1.SelectedPath)
Dim fileInfos() As System.IO.FileInfo
fileInfos = directoryInfo.GetFiles()
For Each fileInfo As System.IO.FileInfo In fileInfos
ListBox1.DataSource = _list
_list.Add(fileInfo.Name)
_list.Sort()
Next
'Refresh Listbox1
ListBox1.DataSource = Nothing
ListBox1.DataSource = _list
You can use data-binding instead of adding the items one by one to the ListBox. I suggest you to add the files to a list first then sort the list and assign it to the ListBox's DataSource.
Define the list a class member
Private _list As New List(Of String)()
Assign it to the ListBox
listBox1.DataSource = _list
Then add new list entry with
_list.Add("new file")
_list.Sort()
' Refresh the ListBox
listBox1.DataSource = Nothing
listBox1.DataSource = _list
UPDATE
If you want to implement your own sorting order then implement a IComparer(Of String)
Class MyFileComparer
Implements IComparer(Of String)
Public Function Compare(x As String, y As String) As Integer _
Implements IComparer(Of String).Compare
Const AlwaysFirst As String = "FILE1"
Dim x = If(x.Contains(AlwaysFirst), "1_", "2_") & x
Dim y = If(y.Contains(AlwaysFirst), "1_", "2_") & y
' Note: If "FILE1" appears always at the end then this would be better
'Dim x = If(x.EndsWith(AlwaysFirst & ".txt"), "1_", "2_") & x
'Dim y = If(y.EndsWith(AlwaysFirst & ".txt"), "1_", "2_") & y
' Normalize strings (e.g. if "File_123.txt" = ""File 123.txt")
x = x.Replace("_"C, " "C)
y = y.Replace("_"C, " "C)
Return x.CompareTo(y)
End Function
End Class
Then you can sort like this
Static comparer = New MyFileComparer()
_list.Sort(comparer)
UPDATE #2
I do not know how your files are named exactly, however if they always end with "FILE<number>.<ext>" you could also change the file name for the string comparison like this:
Original file names
abc_FILE1.txt
abc_123_FILE2.txt
sssd_FILE23.txt
xxx_24_FILE073.txt
Prepared file names
FILE001_abc.txt
FILE002_abc_123.txt
FILE023_sssd.txt
FILE073_xxx_24.txt
Now the Compare method can determine the result simply with
Return x_prepared.CompareTo(y_prepared)
Piggybacking on Olivier's answer, perhaps a Sorted List may work for you?
You also could use OrderBy to sort the items if you need more than an alpha-name sort.
var sorted = from m in myCollection select m orderBy m.FileName;
(syntax may be off)
Related
I am needing to create a code that is versatile enough where I can add more columns in the future with minimum reconstruction of my code. My current code does not allow me to travel through my file with my 2-D array. If I was to change MsgBox("map = "+ map(0,1) I can retrieve the value easily. Currently all I get in the code listed is 'System.IndexOutOfRangeException' and that Index was outside the bounds of the array. My current text file is 15 rows (down) and 2 columns (across) which puts it at a 14x1. they are also comma separated values.
Dim map(14,1) as string
Dim reader As IO.StreamReader
reader = IO.File.OpenText("C:\LocationOfTextFile")
Dim Linie As String, x,y As Integer
For x = 0 To 14
Linie = reader.ReadLine.Trim
For y = 0 To 1
map(x,y) = Split(Linie, ",")(y)
Next 'y
Next 'x
reader.Close()
MsgBox("map = " + map(y,x))``
Here's a generic way to look at reading the file:
Dim data As New List(Of List(Of String))
For Each line As String In IO.File.ReadAllLines("C:\LocationOfTextFile")
data.Add(New List(Of String)(line.Split(",")))
Next
Dim row As Integer = 1
Dim col As Integer = 10
Dim value As String = data(row)(col)
This is the method suggested by Microsoft. It is generic and will work on any properly formatted comma delimited file. It will also catch and display any errors found in the file.
Using MyReader As New Microsoft.VisualBasic.
FileIO.TextFieldParser(
"C:\LocationOfTextFile")
MyReader.TextFieldType = FileIO.FieldType.Delimited
MyReader.SetDelimiters(",")
Dim currentRow As String()
While Not MyReader.EndOfData
Try
currentRow = MyReader.ReadFields()
Dim currentField As String
For Each currentField In currentRow
MsgBox(currentField)
Next
Catch ex As Microsoft.VisualBasic.
FileIO.MalformedLineException
MsgBox("Line " & ex.Message &
"is not valid and will be skipped.")
End Try
End While
End Using
Essentially what you are asking is how can I take the contents of comma-separated values and convert this to a 2D array.
The easiest way, which is not necessarily the best way, is to return an IEnuemrable(Of IEnumerable(Of String)). The number of items will grow both vertically based on the number of lines and the number of items will grow horizontally based on the values split on a respective line by a comma.
Something along these lines:
Private Function GetMap(path As String) As IEnumerable(Of IEnumerable(Of String)
Dim map = New List(Of IEnumerable(Of String))()
Dim lines = IO.File.ReadAllLines(path)
For Each line In lines
Dim row = New List(Of String)()
Dim values = line.Split(","c)
row.AddRange(values)
map.Add(row)
Next
Return map
End Function
Now when you want to grab a specific cell using the (row, column) syntax, you could use:
Private _map As IEnumerable(Of IEnumerable(Of String))
Private Sub LoadMap()
_map = GetMap("C:/path-to-map")
End Sub
Private Function GetCell(row As Integer, column As Integer) As String
If (_map Is Nothing) Then
LoadMap()
End If
Return _map.ElementAt(row).ElementAt(column)
End Function
Here is an example: https://dotnetfiddle.net/ZmY5Ki
Keep in mind that there are some issues with this, for example:
What if you have commas in your cells?
What if you try to access a cell that doesn't exist?
These are considerations you need to make when implementing this in more detail.
You can consider the DataTable class for this. It uses much more memory than an array, but gives you a lot of versatility in adding columns, filtering, etc. You can also access columns by name rather than index.
You can bind to a DataGridView for visualizing the data.
It is something like an in-memory database.
This is much like #Idle_Mind's suggestion, but saves an array copy operation and at least one allocation per row by using an array, rather than a list, for the individual rows:
Dim data = File.ReadLines("C:\LocationOfTextFile").
Select(Function(ln) ln.Split(","c)).
ToList()
' Show last row and column:
Dim lastRow As Integer = data.Count - 1
Dim lastCol As Integer = data(row).Length - 1
MsgBox($"map = {data(lastRow)(lastCol)}")
Here, assuming Option Infer, the data variable will be a List(Of String())
As a step up from this, you could also define a class with fields corresponding to the expected CSV columns, and map the array elements to the class properties as another call to .Select() before calling .ToList().
But what I really recommend is getting a dedicated CSV parser from NuGet. While a given CSV source is usually consistent, more broadly the format is known for having a number of edge cases that can easily confound the Split() function. Therefore you tend to get better performance and consistency from a dedicated parser, and NuGet has several good options.
I use a wordcloud based on a list of words and their frequencies. I load the list from a text file and display them in a Listview and image. When the textfile is not indexed (the highest frequencies first) the word cloud doesn't make the words with the highest counts the biggest.
Is there a way to load the words, highest frequencies first, without having to change the list?
Imports WordCloudGen = WordCloud.WordCloud
Imports System.IO
Public Class WordCloud
Private Sub WordCloud_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Dim lines = File.ReadLines("C:\Users\Gebruiker\Downloads\Words.txt")
Dim Words As New List(Of String) '({100})
Dim Frequencies As New List(Of Integer) '({100})
Dim textValue As String()
Dim items As New List(Of ListViewItem)
For Each line In lines
textValue = line.Split(New Char() {","})
Words.Add(textValue(0))
Frequencies.Add(Integer.Parse(textValue(1)))
items.Add(New ListViewItem(New String() {textValue(0).ToString, textValue(1).ToString}, 0))
Next
ListView1.Items.AddRange(items.ToArray)
Dim wc As WordCloudGen = New WordCloudGen(600, 400)
Dim i As Image = wc.Draw(Words, Frequencies)
ResultPictureBox.Image = i
End Sub
When the textfile is not indexed (the highest frequencies first) the word cloud doesn't make the words with the highest counts the biggest. Is there a way to load the words, highest frequencies first, without having to change the list?
I would recommend a new class to hold your data then you can sort anything you need much easier.
Create a new class: WordsFrequencies
Public Class WordsFrequencies
Public Property Word As String
Public Property Frequency As Integer
End Class
Change your WordCloud_Load routine as below:
Dim WordsFreqList As New List(Of WordsFrequencies)
For Each line As String In File.ReadLines("C:\Users\Gebruiker\Downloads\Words.txt")
Dim splitText As String() = line.Split(","c)
If splitText IsNot Nothing AndAlso splitText.Length = 2 Then
Dim wordFrq As New WordsFrequencies
Dim freq As Integer
wordFrq.Word = splitText(0)
wordFrq.Frequency = If(Integer.TryParse(splitText(1), freq), freq, 0)
WordsFreqList.Add(wordFrq)
End If
Next
If WordsFreqList.Count > 0 Then
' Order the list based on the Frequency
WordsFreqList = WordsFreqList.OrderByDescending(Function(w) w.Frequency).ToList
' Add the sorted items to the listview
WordsFreqList.ForEach(Sub(wf)
ListView1.Items.Add(New ListViewItem(New String() {wf.Word, wf.Frequency.ToString}, 0))
End Sub)
End If
In the above, I would recommend doing a simple For loop with File.ReadLines, this is so you don't have to load the whole file in memory if you're just getting data and parsing it. I'm using the OrderByDescending Method which is part of System.Linq namespace.
As far as this: Dim i As Image = wc.Draw(Words, Frequencies) you then could do something like:
Dim i As Image = wc.Draw(WordsFreqList.Select(Function(wf) wf.Word), WordsFreqList.Select(Function(wf) wf.Frequency))
This will project the Word's into an IEnumerable(String) and then Frequency into an IEnumerable(Integer).
I have some two column data that I read from a file and put into a list then sort alphabetically.
//The file
Hummus,0.75
Chili,0.50
Tabouli,1.25
Tzatziki,0.50
//Declaring the variables and public properties
Dim extraList As List(Of extra)
Public Class extra
Implements IComparable(Of extra)
Public Property Name As String
Public Property Price As Decimal
'Public Property extraList As List(Of extra)
Public Function CompareTo(other As extra) As Integer Implements IComparable(Of extra).CompareTo
Return Me.Name.CompareTo(other.Name)
End Function
End Class
//Puts the data into a list and sorts it
Sub Get_Extras_List()
'Reads the extras file and puts the information into a list, splitting the name of the extra and the price into separate columns
Dim allExtras = From line In System.IO.File.ReadLines("C:\Users\ExtrasList.txt")
Let Columns = line.Split(","c)
Where Columns.Length = 2
Let Price = Decimal.Parse(Columns(1).Trim())
Let Name = Columns(0).Trim()
Select New extra With {.Name = Name, .Price = Price}
extraList = allExtras.ToList()
'Sort the list alphabetically
extraList.Sort()
End Sub
Now I need to code a method that allows the user to type in an extra and search for it using a binary search to see if it exists. So far I have tried this but it just doesn't work and even if it did how do I get it to return a true or false value? (If it exists or not?)
Sub Search_Extras_List()
Dim strSearchExtra As String = Console.ReadLine()
Console.WriteLine(vbLf & "BinarySearch for '{0}':", strSearchExtra)
Dim index As Integer =
List(Of extra).BinarySearch(extraList.Name, strSearchExtra)
End Sub
Finally I have to get the user to choose one of the extras and then add the price of it to the total price. How do I refer to the price? extraList.Price? extra.Price? etc.
If you want to do a binary search like that, you will need to write a comparer.
Referring to List(Of T).BinarySearch Method (T, IComparer(Of T)), it could be
Public Class ExtraComparer
Implements IComparer(Of extra)
Public Function Compare(ByVal x As extra, ByVal y As extra) As Integer Implements IComparer(Of extra).Compare
If x Is Nothing Then
If y Is Nothing Then
' If x is Nothing and y is Nothing, they're equal.
Return 0
Else
' If x is Nothing and y is not Nothing, y is greater.
Return -1
End If
Else
' If x is not Nothing...
If y Is Nothing Then
' ...and y is Nothing, x is greater.
Return 1
Else
' ...and y is not Nothing, compare the names of the two extras.
'
Return x.Name.CompareTo(y.Name)
End If
End If
End Function
End Class
Which you can test with
' Get some item from the data so we know it is present...
Dim a = extraList(2).Name
Dim lookFor As New extra With {.Name = a}
Dim idx = extraList.BinarySearch(lookFor, New ExtraComparer)
Console.WriteLine($"Index of {a} is {idx}.")
(although you would probably want to do a case-insensitive string comparison).
If the index returned is negative then the item was not found. (See the documentation linked to above for more details.)
However, you might find it easier to use LINQ:
Dim a = extraList(2).Name
Dim chosenExtra = extraList.FirstOrDefault(Function(x) x.Name.Equals(a, StringComparison.CurrentCultureIgnoreCase))
If chosenExtra IsNot Nothing Then
Console.WriteLine($"User chose {chosenExtra.Name} at a price of {chosenExtra.Price}")
Else
Console.WriteLine($"User's choice of ""{a}"" was not found.")
End If
I used a case-insensitive comparison in there.
Or Just present the user with a dropdown of the available extras so that they don't have to type it.
I'm trying to add "file type" and "last modified" to my Listview when adding items in It same as in Explorer, but I don't find what property should be assigned to SubItem. Here is my code:
For Each MyFile As IO.FileInfo In ItemDirectory.GetFiles
Dim lvi As New ListViewItem
lvi.Tag = mFile.FullName
lvi.Text = mFile.Name
lvi.ImageKey = CacheShellIcon(mFile.FullName)
Listview1.Items.Add(lvi)
lvi.SubItems.Add("File type ??")
lvi.SubItems.Add(mFile.LastAccessTime.ToShortDateString & " " & mFile.LastAccessTime.ToShortTimeString) 'This isn't same as last modified ?
Next
If somebody knows how to do It please let me know, I want to have this in my Details view.
The linked answer provides an all-purpose way to get all the extended properties. With 300+ elements in newer Windows versions it is clearly overkill to fetch them all if you are only interested in one or two. This returns just the file type. A better approach might be to pass a "shopping list" of desired property names.
As before, you need to add a reference to Microsoft Shell Controls and Automation or Microsoft Shell Folder View Router based on your OS version.
Imports Shell32
Imports SHDocVw
Partial Friend Class Shell32Methods
Friend Shared Function GetShellFileProperty(filepath As String, index As Int32) As String
Dim shell As New Shell32.Shell
Dim shFolder As Shell32.Folder
shFolder = shell.NameSpace(Path.GetDirectoryName(filepath))
' get shell data for this file, cast to folder item
Dim shFolderItem = DirectCast(shFolder.Items().Item(Path.GetFileName(filepath)),
Shell32.ShellFolderItem)
If shFolderItem IsNot Nothing Then
Return shFolder.GetDetailsOf(shFolderItem, index)
Else
Return String.Empty
End If
End Function
...
End Class
Usage:
Dim lvi As ListViewItem
Dim fileType As String
For Each f As String In Directory.EnumerateFiles("C:\Temp\ShellTest")
fileType = Shell32Methods.GetShellFileProperty(f, 9)
lvi = New ListViewItem
lvi.Text = Path.GetFileName(f)
lvi.SubItems.Add(fileType)
lvFiles.Items.Add(lvi)
Next
Ideally, you'd want to create an Enum for the properties so the code could avoid magic numbers:
fileType = Shell32Methods.GetShellFileProperty(f, Shell32FileProps.FileType)
As noted elsewhere, the index of the ones >260 or so can change depending on the OS version. That could be easily modified to accept an Enum/Int array and return a list of values so as to prevent iterating all 300+ propertied to get one or three.
For filetype you can use lvi.SubItems.Add(MyFile.Extension)
and for the "last modified" date, of course the last modified! :D
lvi.SubItems.Add(MyFile.LastWriteTime.ToShortDateString)
Last write and last access are not the same ;)
I figured out another solution, I think this one is easier, at least for me :
Public Function ExProperty(filepath As String, PropertyItem As Integer)
Dim arrHeaders As New List(Of String)()
Dim shell As New Shell
Dim rFolder As Folder = shell.[NameSpace](Path.GetDirectoryName(filepath))
Dim rFiles As FolderItem = rFolder.ParseName(Path.GetFileName(filepath))
'I needed only File type so I looped to 2 only (2 is the file type in my case - Windows 10 -
' to see all available properties do a loop
' 0 To Short.MaxValue - 1" and then extract whatever property you like)
For i As Integer = 0 To 2
Dim value As String = rFolder.GetDetailsOf(rFiles, i).Trim()
arrHeaders.Add(value)
Next
Dim DesiredProperty As String
DesiredProperty = arrHeaders.Item(PropertyItem)
Return DesiredProperty
End Function
Usage with Listview just simply (this adds File type subitem):
Listview1_Item.SubItems.Add(ExProperty(filepath, 2))
As in all solutions, a reference to Microsoft Shell Controls and Automation must be set.
I've seen a couple of posts asking a similar question but I have not been able to duplicate the answers in my code successfully.
The following code adds items and their value member to a list box.
Public Shared Sub ListFiles(hTab As Hashtable)
Debug.Print("create file and key" & Now)
Dim Enumerator As IDictionaryEnumerator
Enumerator = hTab.GetEnumerator()
Dim MyKeys As ICollection
Dim Key As Object
MyKeys = hTab.Keys()
If (hTab.Count > 0) Then
For Each Key In MyKeys
Dim sfileName As String = hTab(Key)
Dim first As Integer = sfileName.IndexOf("_")
Dim last As Integer = sfileName.LastIndexOfAny("_")
Dim first2 = (first + 1)
Dim splitFile = sfileName.Substring(first2)
frmViewFiles.ListBox1.Items.Add(splitFile)
frmViewFiles.ListBox1.ValueMember = Key
frmViewFiles.ListBox1.SelectedValue = Key
Next
End If
End Sub
When I run my code to get the selected items value member
Dim file = ListBox1.ValueMember.ToString()
I can acess the first item I choose but subsequent selections dont change the value member to that of the selected item.
Please direct me.
Thank you for your answers. this is my new code:
Public Shared Sub runListFiles(CustomerId As String)
Dim cfp As New CloudFilesProvider(cloudId)
Dim containerObjectList As IEnumerable(Of ContainerObject) = cfp.ListObjects(container:="EstherTest", identity:=cloudId, prefix:=CustomerId & "_")
For Each file As ContainerObject In containerObjectList
Dim sFullFileName As String = file.Name
Dim first As Integer = sFullFileName.IndexOf("_")
Dim first2 = (first + 1)
Dim splitFile = sFullFileName.Substring(first2)
'frmViewFiles.ListBox1.Items.Add(splitFile)
'frmViewFiles.ListBox1.ValueMember = sFullFileName
Dim fb = New myFile
fb.FileName = splitFile
fb.FullPath = sFullFileName
frmViewFiles.ListBox1.Items.Add(fb)
frmViewFiles.ListBox1.DisplayMember = fb.FileName
frmViewFiles.ListBox1.ValueMember = fb.FullPath
This is my class:
Public Class myFile
Public Property FileName As String
Public Property FullPath As String
Public Sub New(f As String, b As String)
FileName = f
FullPath = b
End Sub
End Class
Please see my comment below and assist
ValueMember is supposed to indicate the property name of an object added to the Items collection: the property to use as the actual value for the items in the ListControl.
You are not adding objects to the control, so Key from the hashtable is meaningless as the ValueMember. Your post references a file variable in passing, so I will assume this revolves around showing the filename while wanting to get the full pathname when selected/clicked. WebForms/Winforms/WPF was not indicated, I am assuming WinForms:
Public Class myFile
Public Property FileName As String
Public Property FullPath As String
Public Property FileSize As Int64 ' just so there is something else
Public Sub New(f as String, p as String, s as Int64)
FileName = f
FullPath = b
FileSize = s
End Sub
End Class
Lets say we want to add some of these to a ListBox, for each item added we want FileName to display as the text, but want to get them back by FullPath:
Dim f As myFile
' assume these come from a fileinfo
For Each fi as FileInfo in DirectoryInfo.GetFiles(searchFor)
f = New myFile
f.FileName = fi.Name
f.FullPath = fi.FullPath
f.FileSize = fi.Length
' myFile accepts all the prop values in the constructor
' so creating a new one could also be written as:
' f = New myFile(fi.Name, fi.FullPath, fi.Length)
myListBox.Items.Add(f)
Next n
If the myFile objects were stored to a List(of myFile) rather than adding them to the control, we can bind the List as the DataSource and not have to iterate or copy:
mylistBox.DataSource = myFileList
Either way, Display- and ValueMember refer to the property names we wish to use:
myListBox.DisplayMember = "FileName" ' indicate property name of obj to SHOW
myListBox.ValueMember = "FullPath" ' prop name of object to return
When you select a listbox item, myListBox.SelectedValue would refer to the FullPath of the myFile object clicked on. The SelectedIndex would still refer to the index of the item in the list.
tl;dr
ValueMember and DisplayMember refers to the Property Names of Objects represented in the list.
Note:
I know this is many years later, but still relevant information.
It took me a while to parse what was said above, until I grokked it fully, so I thought it might help if I restated it slightly.
When you select a listbox item,
myListBox.SelectedValue is the contents of the field, myListBox.ValueMember. ValueMember contains the Field Name, SelectedValue contains the contents of the field.
myListBox.SelectedItem is the contents of the field myListBox.DisplayMember. DisplayMember contains the field name and SelectedItem contains the value of the field.
The SelectedIndex refers to the index of the item in the list. To see which item is selected, reference myListBox.SelectedIndex. You can, for example, change the selection to the last item in the list by using myListBox.SelectedIndex = myListBox.Items.Count - 1
If you want to display the values, then
Console.WriteLine("The value of {0} is {1}",myListBoxDisplayMember,myListBox.SelectedItem)
Console.WriteLine("The Value of {0} is {1}",myListBox.ValueMember,myListBox.SelectedValue)