如何以编程方式打印PrintDocument中的特定页面？

Question

是否有一种方法可以通过编程方式仅打印System.Drawing.Printing.PrintDocument中选定的页面(例如，第3-5页)？

我使用的是以下代码：

myPrintDocument.Print();

但这样我就不能以编程方式跳过页面。我考虑过这样一种可能性:显示一个modified version of the PrintDialog class，跳过我不想要的页面，打印文档，并以编程方式关闭PrintDialog窗口(这样它只会闪过)。但这将是一种黑客行为。

Answer 1

您可以在PrintDocument.BeginPrint事件中设置PrinterSettings。

打印控制器将为PrinterSettings中设置的直到最后一页的每一页引发PrintDocument.PrintPage事件，您将在其中放置打印代码。例如，如果您有一个10页的PrintDocument，并且您设置了PrintDocument.PrinterSettings.ToPage = 5，那么打印控制器将为每一页引发PrintPage事件，直到它处理第5页。

如果要跳过页面，例如从PrinterSettings.FromPage =3到ToPage = 5，则打印控制器将引发3次PrintPage事件。这是从3到5(包括3到5)的每个计数一个PrintPage事件。

打印控制器不决定PrintPage事件要打印的内容。它只在您的范围内的每个计数页引发一次事件。例如，如果您将FromPage =4指定为FromPage = 6，则打印控制器将引发完全相同数量的PrintPage事件，但它甚至不知道其中的区别！它不知道使用PrintPage事件打印的是哪一页。它只知道引发PrintPage事件3次。

我的观点是，PrintPage事件中的代码必须处理所有跳过的页面，而不绘制任何内容。然后，同一PrintPage事件中的代码必须处理并绘制要打印的“当前页”，然后返回，以便打印控制器可以引发下一个PrintPage事件。

下面是伪代码：

void Setup_Printing()
{
  myPrintDocument.BeginPrint += On_BeginPrint;
  myPrintDocument.PrintPage += On_PrintPage;
}

// Page Index variable
int indexCuurentPage = 0;

void On_BeginPrint(object sender, PrintEventArgs e)
{
  indexCuurentPage = 0;
  ((PrintDocument)sender).PrinterSettings.PrintRange = PrintRange.SomePages;
  ((PrintDocument)sender).PrinterSettings.FromPage = 3;
  ((PrintDocument)sender).PrinterSettings.ToPage = 5;
}


void On_PrintPage(object sender, PrintPageEventArgs ppea)
{
  // Set up a loop to process pages.
  bool bProcessingPages = true;
  while (bProcessingPages)
  {
    indexCurrentPage++;

    // Set isPageInRange flag to true if this indexCurrentPage is in the selected range of pages
    bool isPageInRange = (theCurrentPage >= ppea.PageSettings.PrinterSettings.FromPage);
    isPageInRange = isPageInRange && (theCurrentPage =< ppea.PageSettings.PrinterSettings.ToPage);

    if (isPageInRange)
    {
      // Process your data and print this page then exit the loop.  
      try
      {
        //// TO DO - Process Data ////
        //// TO DO - Draw Data to ppea.Graphics ////
        // Note:  Do not set the ppea.HasMorePages to true.  Let the Printer Controller do it.
      }
      catch
      {
        // Abort printing more pages if there was an error.
        ppea.HasMorePages = false;
      }
      // Set the loop exit flag.  We could use "return;" instead if we do not want to do more.
      bProcessingPages = false;
    }
    else
    {
      // Process your data and Do Not Draw on the ppea.Graphics.
      try
      {
        //// TO DO - Process Data ////
      }
      catch
      {
        // Abort printing more pages if there was an error.
        ppea.HasMorePages = false;
        // Set the loop exit flag.  We could use "return;" instead if we do not want to do more.
        bProcessingPages = false;
      }
      // Stay in the processing loop until you either need to actually Print a Page
      // or until you run out of data and pages to print.
    }

    // check to see if we ran out of pages to print
    if (indexCurrentPage >= ppea.PageSettings.PrinterSettings.ToPage)
    {
      // Done.  We do not need to set the HasMorePages = false
      bProcessingPages = false;
    }
  } // end while processing pages

  // The print controller will decide to raise the next PrintPage event if it needs to.
  // If You set the ppea.HasMorePages = false, then it will stop any more page events. 
  // If You set the ppea.HasMorePages = true, 
  //    then I'm not sure what the print controller will do if it ran out of pages!
}

Answer 2

像这样的怎么样？

PrinterSettings printSettings = new PrinterSettings()
            {
                FromPage = 3,
                ToPage = 5
            };
PrintDocument myPrintDocument = new PrintDocument()
            {
                PrinterSettings = printSettings
            };
myPrintDocument.Print();