mamen
29-03-2007, 14:27:30
Hola a todos necesito ayuda urgente, me estoy volviendo loca con este tema. Estoy utilizando la clase PrintDocument para imprimir un archivo q tengo en memoria en un MemoryStream, pero el ejemplo viene en visual basic mis preguntas son:
1. No entiendo cómo relaciona el PrintDocument con el StreamReader.
2. Esta linea de codigo
AddHandler pd.PrintPage, AddressOf Me.pd_PrintPage
cómo se traduce a delphi.
3. Cómo se asocia el parametro ev As PrintPageEventArgs del método pd_PrintPage
Por favor, agradecería que alguien me pudiera ayudar. Muchas gracias por adelantado. El código completo lo adjunto a continuacion.
CODIGO COMPLETO
Public Class PrintingExample
Inherits System.Windows.Forms.Form
Private components As System.ComponentModel.Container
Private printButton As System.Windows.Forms.Button
Private printFont As Font
Private streamToPrint As StreamReader
Public Sub New()
' The Windows Forms Designer requires the following call.
InitializeComponent()
End Sub
' The Click event is raised when the user clicks the Print button.
Private Sub printButton_Click(sender As Object, e As EventArgs)
Try
streamToPrint = New StreamReader("C:\My Documents\MyFile.txt")
Try
printFont = New Font("Arial", 10)
Dim pd As New PrintDocument()
AddHandler pd.PrintPage, AddressOf Me.pd_PrintPage
pd.Print()
Finally
streamToPrint.Close()
End Try
Catch ex As Exception
MessageBox.Show(ex.Message)
End Try
End Sub
' The PrintPage event is raised for each page to be printed.
Private Sub pd_PrintPage(sender As Object, ev As PrintPageEventArgs)
Dim linesPerPage As Single = 0
Dim yPos As Single = 0
Dim count As Integer = 0
Dim leftMargin As Single = ev.MarginBounds.Left
Dim topMargin As Single = ev.MarginBounds.Top
Dim line As String = Nothing
' Calculate the number of lines per page.
linesPerPage = ev.MarginBounds.Height / printFont.GetHeight(ev.Graphics)
' Print each line of the file.
While count < linesPerPage
line = streamToPrint.ReadLine()
If line Is Nothing Then
Exit While
End If
yPos = topMargin + count * printFont.GetHeight(ev.Graphics)
ev.Graphics.DrawString(line, printFont, Brushes.Black, leftMargin, yPos, New StringFormat())
count += 1
End While
' If more lines exist, print another page.
If Not (line Is Nothing) Then
ev.HasMorePages = True
Else
ev.HasMorePages = False
End If
End Sub
1. No entiendo cómo relaciona el PrintDocument con el StreamReader.
2. Esta linea de codigo
AddHandler pd.PrintPage, AddressOf Me.pd_PrintPage
cómo se traduce a delphi.
3. Cómo se asocia el parametro ev As PrintPageEventArgs del método pd_PrintPage
Por favor, agradecería que alguien me pudiera ayudar. Muchas gracias por adelantado. El código completo lo adjunto a continuacion.
CODIGO COMPLETO
Public Class PrintingExample
Inherits System.Windows.Forms.Form
Private components As System.ComponentModel.Container
Private printButton As System.Windows.Forms.Button
Private printFont As Font
Private streamToPrint As StreamReader
Public Sub New()
' The Windows Forms Designer requires the following call.
InitializeComponent()
End Sub
' The Click event is raised when the user clicks the Print button.
Private Sub printButton_Click(sender As Object, e As EventArgs)
Try
streamToPrint = New StreamReader("C:\My Documents\MyFile.txt")
Try
printFont = New Font("Arial", 10)
Dim pd As New PrintDocument()
AddHandler pd.PrintPage, AddressOf Me.pd_PrintPage
pd.Print()
Finally
streamToPrint.Close()
End Try
Catch ex As Exception
MessageBox.Show(ex.Message)
End Try
End Sub
' The PrintPage event is raised for each page to be printed.
Private Sub pd_PrintPage(sender As Object, ev As PrintPageEventArgs)
Dim linesPerPage As Single = 0
Dim yPos As Single = 0
Dim count As Integer = 0
Dim leftMargin As Single = ev.MarginBounds.Left
Dim topMargin As Single = ev.MarginBounds.Top
Dim line As String = Nothing
' Calculate the number of lines per page.
linesPerPage = ev.MarginBounds.Height / printFont.GetHeight(ev.Graphics)
' Print each line of the file.
While count < linesPerPage
line = streamToPrint.ReadLine()
If line Is Nothing Then
Exit While
End If
yPos = topMargin + count * printFont.GetHeight(ev.Graphics)
ev.Graphics.DrawString(line, printFont, Brushes.Black, leftMargin, yPos, New StringFormat())
count += 1
End While
' If more lines exist, print another page.
If Not (line Is Nothing) Then
ev.HasMorePages = True
Else
ev.HasMorePages = False
End If
End Sub