PrintDocument.PrintPage 事件

定义

当需要为当前页打印的输出时发生。Occurs when the output to print for the current page is needed.

public:
 event System::Drawing::Printing::PrintPageEventHandler ^ PrintPage;
public event System.Drawing.Printing.PrintPageEventHandler PrintPage;
member this.PrintPage : System.Drawing.Printing.PrintPageEventHandler 
Public Custom Event PrintPage As PrintPageEventHandler 

示例

下面的代码示例演示如何处理 PrintPage 事件。The following code example demonstrates handling the PrintPage event.

有关其他示例,请参阅如何:在 Windows 窗体中打印多页文本文件For another example, see How to: Print a Multi-Page Text File in Windows Forms.


#using <System.dll>
#using <System.Windows.Forms.dll>
#using <System.Drawing.dll>

using namespace System;
using namespace System::IO;
using namespace System::Drawing;
using namespace System::Drawing::Printing;
using namespace System::Windows::Forms;

public ref class PrintingExample: public System::Windows::Forms::Form
{
private:
   System::ComponentModel::Container^ components;
   System::Windows::Forms::Button^ printButton;
   System::Drawing::Font^ printFont;
   StreamReader^ streamToPrint;

public:
   PrintingExample()
      : Form()
   {
      
      // The Windows Forms Designer requires the following call.
      InitializeComponent();
   }


private:

   // The Click event is raised when the user clicks the Print button.
   void printButton_Click( Object^ /*sender*/, EventArgs^ /*e*/ )
   {
      try
      {
         streamToPrint = gcnew StreamReader( "C:\\My Documents\\MyFile.txt" );
         try
         {
            printFont = gcnew System::Drawing::Font( "Arial",10 );
            PrintDocument^ pd = gcnew PrintDocument;
            pd->PrintPage += gcnew PrintPageEventHandler( this, &PrintingExample::pd_PrintPage );
            pd->Print();
         }
         finally
         {
            streamToPrint->Close();
         }

      }
      catch ( Exception^ ex ) 
      {
         MessageBox::Show( ex->Message );
      }

   }


   // The PrintPage event is raised for each page to be printed.
   void pd_PrintPage( Object^ /*sender*/, PrintPageEventArgs^ ev )
   {
      float linesPerPage = 0;
      float yPos = 0;
      int count = 0;
      float leftMargin = (float)ev->MarginBounds.Left;
      float topMargin = (float)ev->MarginBounds.Top;
      String^ line = nullptr;
      
      // 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()) != nullptr) )
      {
         yPos = topMargin + (count * printFont->GetHeight( ev->Graphics ));
         ev->Graphics->DrawString( line, printFont, Brushes::Black, leftMargin, yPos, gcnew StringFormat );
         count++;
      }

      
      // If more lines exist, print another page.
      if ( line != nullptr )
            ev->HasMorePages = true;
      else
            ev->HasMorePages = false;
   }


   // The Windows Forms Designer requires the following procedure.
   void InitializeComponent()
   {
      this->components = gcnew System::ComponentModel::Container;
      this->printButton = gcnew System::Windows::Forms::Button;
      this->ClientSize = System::Drawing::Size( 504, 381 );
      this->Text = "Print Example";
      printButton->ImageAlign = System::Drawing::ContentAlignment::MiddleLeft;
      printButton->Location = System::Drawing::Point( 32, 110 );
      printButton->FlatStyle = System::Windows::Forms::FlatStyle::Flat;
      printButton->TabIndex = 0;
      printButton->Text = "Print the file.";
      printButton->Size = System::Drawing::Size( 136, 40 );
      printButton->Click += gcnew System::EventHandler( this, &PrintingExample::printButton_Click );
      this->Controls->Add( printButton );
   }

};


// This is the main entry point for the application.
int main()
{
   Application::Run( gcnew PrintingExample );
}

using System;
using System.IO;
using System.Drawing;
using System.Drawing.Printing;
using System.Windows.Forms;

public partial class Form1 : System.Windows.Forms.Form
{
    private System.ComponentModel.Container components;
    private System.Windows.Forms.Button printButton;
    private Font printFont;
    private StreamReader streamToPrint;

    public Form1()
    {
        // The Windows Forms Designer requires the following call.
        InitializeComponent();
    }

    // The Click event is raised when the user clicks the Print button.
    private void printButton_Click(object sender, EventArgs e)
    {
        try
        {
            streamToPrint = new StreamReader
               ("C:\\My Documents\\MyFile.txt");
            try
            {
                printFont = new Font("Arial", 10);
                PrintDocument pd = new PrintDocument();
                pd.PrintPage += new PrintPageEventHandler
                   (this.pd_PrintPage);
                pd.Print();
            }
            finally
            {
                streamToPrint.Close();
            }
        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.Message);
        }
    }

    // The PrintPage event is raised for each page to be printed.
    private void pd_PrintPage(object sender, PrintPageEventArgs ev)
    {
        float linesPerPage = 0;
        float yPos = 0;
        int count = 0;
        float leftMargin = ev.MarginBounds.Left;
        float topMargin = ev.MarginBounds.Top;
        string line = null;

        // 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()) != null))
        {
            yPos = topMargin + (count *
               printFont.GetHeight(ev.Graphics));
            ev.Graphics.DrawString(line, printFont, Brushes.Black,
               leftMargin, yPos, new StringFormat());
            count++;
        }

        // If more lines exist, print another page.
        if (line != null)
            ev.HasMorePages = true;
        else
            ev.HasMorePages = false;
    }

    // The Windows Forms Designer requires the following procedure.
    private void InitializeComponent()
    {
        this.components = new System.ComponentModel.Container();
        this.printButton = new System.Windows.Forms.Button();

        this.ClientSize = new System.Drawing.Size(504, 381);
        this.Text = "Print Example";

        printButton.ImageAlign =
           System.Drawing.ContentAlignment.MiddleLeft;
        printButton.Location = new System.Drawing.Point(32, 110);
        printButton.FlatStyle = System.Windows.Forms.FlatStyle.Flat;
        printButton.TabIndex = 0;
        printButton.Text = "Print the file.";
        printButton.Size = new System.Drawing.Size(136, 40);
        printButton.Click += new System.EventHandler(printButton_Click);

        this.Controls.Add(printButton);
    }
}

Imports System.IO
Imports System.Drawing
Imports System.Drawing.Printing
Imports System.Windows.Forms

Public Class Form1
    Inherits System.Windows.Forms.Form
    Private WithEvents 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()
        InitializeForm()
    End Sub

    ' The Click event is raised when the user clicks the Print button.
    Private Sub printButton_Click(ByVal sender As Object, ByVal e As EventArgs) Handles printButton.Click
        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(ByVal sender As Object, ByVal 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 (line IsNot Nothing) Then
            ev.HasMorePages = True
        Else
            ev.HasMorePages = False
        End If
    End Sub

    Private Sub InitializeForm()
        Me.components = New System.ComponentModel.Container()
        Me.printButton = New System.Windows.Forms.Button()

        Me.ClientSize = New System.Drawing.Size(504, 381)
        Me.Text = "Print Example"

        printButton.ImageAlign = System.Drawing.ContentAlignment.MiddleLeft
        printButton.Location = New System.Drawing.Point(32, 110)
        printButton.FlatStyle = System.Windows.Forms.FlatStyle.Flat
        printButton.TabIndex = 0
        printButton.Text = "Print the file."
        printButton.Size = New System.Drawing.Size(136, 40)
        AddHandler printButton.Click, AddressOf printButton_Click

        Me.Controls.Add(printButton)
    End Sub


    ' This is the main entry point for the application.    
    Public Shared Sub Main()
        Application.Run(New Form1())
    End Sub

End Class

注解

若要指定要打印的输出,请使用 GraphicsPrintPageEventArgs 属性。To specify the output to print, use the Graphics property of the PrintPageEventArgs. 例如,若要指定应打印的文本行,请使用 Graphics.DrawString 方法绘制文本。For example, to specify a line of text that should be printed, draw the text using the Graphics.DrawString method.

除了指定输出之外,还可以通过将 PrintPageEventArgs.HasMorePages 属性设置为 true来指示是否有其他要打印的页面。In addition to specifying the output, you can indicate if there are additional pages to print by setting the PrintPageEventArgs.HasMorePages property to true. 默认值为 false,这表示没有要打印的页面。The default is false, which indicates that there are no more pages to print. 还可以通过 PageSettings 修改各个页面设置,通过将 PrintPageEventArgs.Cancel 属性设置为 true,可以取消打印作业。Individual page settings can also be modified through the PageSettings and the print job can be canceled by setting the PrintPageEventArgs.Cancel property to true. 若要使用不同的页面设置打印文档的每一页,请处理 QueryPageSettings 事件。To print each page of a document using different page settings, handle the QueryPageSettings event.

若要将事件与事件处理程序关联,请将 PrintPageEventHandler 委托的实例添加到事件。To associate the event with your event handler, add an instance of the PrintPageEventHandler delegate to the event. 每当发生事件时,就会调用事件处理程序。The event handler is called whenever the event occurs. 有关用委托处理事件的详细信息,请参阅处理和引发事件For more information about handling events with delegates, see Handling and Raising Events.

适用于

另请参阅