VB.NET Print total items of ListBox

[mikeg71]

Trying to print the complete list of items from a listbox using this code. When I set 'e.HasMorePages' to True, it will continue to run on forever. Not sure what I am missing here, but the way this is now only gives me a single page of items. Thanks for any assistance on this.

    Private Sub BtnPrint_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnPrint.Click
        PrintDocument1.Print()
    End Sub

    Private Sub PrintDocument1_PrintPage(ByVal sender As System.Object, ByVal e As System.Drawing.Printing.PrintPageEventArgs) Handles PrintDocument1.PrintPage

        Dim fnt As New Font("Arial", 10, FontStyle.Regular, GraphicsUnit.Point)
        Dim ListBoxItem As String = String.Empty

        For Each LBItem As String In ListBox2.Items
            ListBoxItem = ListBoxItem & vbCrLf & LBItem
        Next

        ListBoxItem = ListBoxItem.Substring(vbCrLf.Length)
        e.Graphics.DrawString(ListBoxItem, fnt, Brushes.Black, 0, 0)
        e.HasMorePages = False

    End Sub

[dday9]

Printing is a bit difficult. Basically what you will need to do is draw the String of each item in the ListBox and if the total height of all that has been drawn will exceed the total height of the page then you need to set HasMorePages to true.

Try something like this (untested and modified from ChatGPT):

Imports System.Drawing.Printing
Public Class MyForm
    Private _startIndex As Integer = 0

    Private Sub PrintDocument1_PrintPage(sender As Object, e As PrintPageEventArgs) Handles PrintDocument1.PrintPage
        Dim printFont = New Font("Arial", 10, FontStyle.Regular, GraphicsUnit.Point)
        Dim lineHeight = printFont.GetHeight(e.Graphics)
        Dim printArea = New RectangleF(e.MarginBounds.Left, e.MarginBounds.Top, e.MarginBounds.Width, e.MarginBounds.Height)
        Dim itemIndex = _startIndex
        Dim listboxItemCount = ListBox2.Items.Count

        While (itemIndex < listboxItemCount)
            Dim itemText = ListBox2.Items(itemIndex).ToString()
            Dim textLayout = New StringFormat()

            printArea.Y += lineHeight

            Dim linesPerPage = Convert.ToInt32(Math.Floor(printArea.Height / lineHeight))

            For i = 0 To linesPerPage - 1
                If (itemIndex < listboxItemCount) Then
                    Dim lineRectangle = New RectangleF(printArea.Left, printArea.Y, printArea.Width, lineHeight)
                    e.Graphics.DrawString(itemText, printFont, Brushes.Black, lineRectangle, textLayout)
                    printArea.Y += lineHeight
                    itemIndex += 1
                Else
                    Exit For
                End If
            Next

            If (itemIndex < listboxItemCount) Then
                e.HasMorePages = True
                _startIndex = itemIndex
                Return
            End If
        End While

        _startIndex = 0
        e.HasMorePages = False
    End Sub
End Class

Update -
Reviewing this code a little bit, it is potentially flawed a little bit based on your situation.

This code assumes that each item in the ListBox only takes up a single line on the printed document. If that's not the case, then you'll need to adjust the lineHeight variable in the For/Next loop to be recalculated the height of the drawn text.

If you don't have any items that span multiple lines though, then this solution should be fine.

[mikeg71]

Thanks dday9... this does produce strange results like you said. My listbox is populated with info after searching multiple files for a part number and returning filename and qty of each part number within. Here is an example of the listbox contents: "PART NUMBER" is what was searched. "-TOP & -BTM" lines are the filenames found containing the part number and then QTY used. The typical print range on this can be 1 to 10 pages.

PART NUMBER:  GR29-028B
_______________________________

2-900-09-TOP
QTY Per = 4
--------------
2-189-02-BTM
QTY Per = 8
--------------
2-3389-01-TOP
QTY Per = 17
--------------
4-988-023-TOP
QTY Per = 12

[dday9]

I'm not fully understanding the issue, could you elaborate a bit more on what happened when you tried the solution I provided?

[mikeg71]

Sorry, I should have posted that as well. Your code now prints like this:

PART NUMBER:  GR29-028B
PART NUMBER:  GR29-028B
PART NUMBER:  GR29-028B
PART NUMBER:  GR29-028B
PART NUMBER:  GR29-028B
PART NUMBER:  GR29-028B
PART NUMBER:  GR29-028B
PART NUMBER:  GR29-028B
PART NUMBER:  GR29-028B
PART NUMBER:  GR29-028B
--------------------------
--------------------------
--------------------------
--------------------------
--------------------------
--------------------------
--------------------------
--------------------------
--------------------------
--------------------------
--------------------------
--------------------------
QTY Per = 5
QTY Per = 5
QTY Per = 5
QTY Per = 5
QTY Per = 5
QTY Per = 5
QTY Per = 5
QTY Per = 5
QTY Per = 5
QTY Per = 5

[dday9]

So this loops over every item in your ListBox. If you setup a debugger at the top of the PrintPage event handler, what is the result of ListBox2.Items?

[wes4dbt]

Looks like your loop is setup wrong. Need to post your current code.

btw - That data really seems to lend itself to being displayed in a DataGridView. Each file would only use one line, not 3. Save a lot of pages.

I believe in the Code Bank there is an example of how to print a datagridview.

[mikeg71]

dday9 - I must be doing this wrong because I cannot get the listbox items to change when I set a breakpoint and step through it.

wes4dbt - I am open to doing a DataGridView rather than a listbox if it makes printing easier. I have it set this way now simply for user readability.

Here is the complete code I am using now to search and populate the listbox. I am certain it lacks efficiency.

Imports System.Drawing.Printing
Imports System.IO
Imports System.Text.RegularExpressions

Public Class Form1

    Dim fpath = Directory.GetCurrentDirectory
    Dim filesPath = fpath
    Dim thePart As String
    Private _startIndex As Integer = 0

    Private Sub BtnSearch_Click(sender As System.Object, e As System.EventArgs) Handles BtnSearch.Click

        If txtPartNum.Text = "" Then Exit Sub

        Me.ListBox2.Items.Clear()

        thePart = $"{txtPartNum.Text}" 'match whole word
        ListBox2.Font = New Font("Arial", 10, FontStyle.Regular)
        Me.ListBox2.Items.Add("PART NUMBER:    " & thePart)
        Me.ListBox2.Items.Add("________________________________________")
        Me.ListBox2.Items.Add("")

        Dim startFolder As String = fpath & "\prg"
        Dim fileList As IEnumerable(Of FileInfo) = GetFiles(startFolder)
        Dim searchTerm As New Regex(thePart)


        Dim queryMatchingFiles = From afile In fileList
                                 Where afile.Extension = ".dp"
                                 Let fileText = File.ReadAllText(afile.FullName)
                                 Let matches = searchTerm.Matches(fileText)
                                 Where (matches.Count > 0)
                                 Select Name = afile.Name,
                                        Matches = From match As Match In matches
                                                  Group By match.Value Into g = Group
                                                  Select New With {Value, g.Count}


        Try
            Dim folder As String = fpath & "\parts\"
            Dim filename As String = System.IO.Path.Combine(folder, thePart & ".jpg")
            PictureBox1.Image = Image.FromFile(filename)
        Catch ex As Exception
            'Leave image blank
        End Try


        For Each fileMatches In queryMatchingFiles
            Dim s = fileMatches.Name
            Dim newFile As String = (Path.Combine(Path.GetDirectoryName(s), Path.GetFileNameWithoutExtension(s)))
            ListBox2.Items.Add(newFile)
            For Each match In fileMatches.Matches
                'ListBox2.Items.Add(match.Value + ": " + match.Count.ToString)
                ListBox2.Items.Add("QTY Per =   " + match.Count.ToString)
            Next
            ListBox2.Items.Add("------------------------------")
        Next

    End Sub

    Shared Function GetFiles(root As String) As IEnumerable(Of FileInfo)
        Return From file In My.Computer.FileSystem.GetFiles(
                   root, FileIO.SearchOption.SearchAllSubDirectories, "*.*")
               Select New FileInfo(file)
    End Function

    Private Sub txtPartNum_KeyPress(sender As Object, e As KeyPressEventArgs) Handles txtPartNum.KeyPress
        If e.KeyChar = Chr(13) Then
            BtnSearch.Focus()
            BtnSearch.PerformClick()
        End If
    End Sub

    Private Sub BtnPrint_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnPrint.Click
        PrintDocument1.Print()
    End Sub

    'Private Sub PrintDocument1_PrintPage(ByVal sender As System.Object, ByVal e As System.Drawing.Printing.PrintPageEventArgs) Handles PrintDocument1.PrintPage

    '    Dim fnt As New Font("Arial", 10, FontStyle.Regular, GraphicsUnit.Point)
    '    Dim ListBoxItem As String = String.Empty

    '    For Each LBItem As String In ListBox2.Items
    '        ListBoxItem = ListBoxItem & vbCrLf & LBItem
    '        ListBoxItem = ListBoxItem.Substring(vbCrLf.Length)
    '    Next

    '    ListBoxItem = ListBoxItem.Substring(vbCrLf.Length)
    '    e.Graphics.DrawString(ListBoxItem, fnt, Brushes.Black, 0, 0)
    '    e.HasMorePages = False

    'End Sub

    Private Sub PrintDocument1_PrintPage(sender As Object, e As PrintPageEventArgs) Handles PrintDocument1.PrintPage
        Dim printFont = New Font("Arial", 10, FontStyle.Regular, GraphicsUnit.Point)
        Dim lineHeight = printFont.GetHeight(e.Graphics)
        Dim printArea = New RectangleF(e.MarginBounds.Left, e.MarginBounds.Top, e.MarginBounds.Width, e.MarginBounds.Height)
        Dim itemIndex = _startIndex
        Dim listboxItemCount = ListBox2.Items.Count

        While (itemIndex < listboxItemCount)
            Dim itemText = ListBox2.Items(itemIndex).ToString()
            Dim textLayout = New StringFormat()

            printArea.Y += lineHeight

            Dim linesPerPage = Convert.ToInt32(Math.Floor(printArea.Height / lineHeight))

            For i = 0 To linesPerPage - 1
                If (itemIndex < listboxItemCount) Then
                    Dim lineRectangle = New RectangleF(printArea.Left, printArea.Y, printArea.Width, lineHeight)
                    e.Graphics.DrawString(itemText, printFont, Brushes.Black, lineRectangle, textLayout)
                    printArea.Y += lineHeight
                    itemIndex += 1
                Else
                    Exit For
                End If
            Next

            If (itemIndex < listboxItemCount) Then
                e.HasMorePages = True
                _startIndex = itemIndex
                Return
            End If
        End While

        _startIndex = 0
        e.HasMorePages = False
    End Sub

End Class

[.paul.]

I’m not sure what data you have in your ListBox. If you do decide to switch to a DataGridView, check the DataGridView Printing link in my signature below this post…

[wes4dbt]

        While (itemIndex < listboxItemCount)
            Dim itemText = ListBox2.Items(itemIndex).ToString()
            Dim textLayout = New StringFormat()

            printArea.Y += lineHeight

            Dim linesPerPage = Convert.ToInt32(Math.Floor(printArea.Height / lineHeight))

            For i = 0 To linesPerPage - 1
                If (itemIndex < listboxItemCount) Then
                    Dim lineRectangle = New RectangleF(printArea.Left, printArea.Y, printArea.Width, lineHeight)
                    e.Graphics.DrawString(itemText, printFont, Brushes.Black, lineRectangle, textLayout)
                    printArea.Y += lineHeight
                    itemIndex += 1
                Else
                    Exit For
                End If
            Next

            If (itemIndex < listboxItemCount) Then
                e.HasMorePages = True
                _startIndex = itemIndex
                Return
            End If
        End While

There is definitely a problem with you For loop. This line just keep printing the same thing over and over. "e.Graphics.DrawString(itemText, printFont, Brushes.Black, lineRectangle, textLayout)"

My guess is it should be something like,

e.Graphics.DrawString(ListBox2.Items(itemIndex).ToString, printFont, Brushes.Black, lineRectangle, textLayout)

That's just a guess, I didn't do any testing.

[mikeg71]

@wes4dbt - Your guess was genius, it works . Thanks so much for your help on this. I honestly did not realize how difficult it was to print the contents of a listbox until this came up. Thanks again!

[mikeg71]

I’m not sure what data you have in your ListBox. If you do decide to switch to a DataGridView, check the DataGridView Printing link in my signature below this post…

@.paul. - I am planning to try out DataGridView as I have never used it for anything. In your experience, is it better than a listbox when just adding smaller amounts of data?

[.paul.]

DGVs are great for displaying and or editing tabular data. They have many properties and are fully (well, within reason) customizable. Listboxes are great if you just want to display data. They don’t work well with tabular data, so no columns…

[mikeg71]

Good info to know. I will for sure look at using the DGV, and even possibly converting this project over to it at some point.