C# PrintDocument打印 多页 打印预览
PrintDocument实例所有的订阅事件如下：
1.创建一个PrintDocument的实例.如下：
System.Drawing.Printing.PrintDocument docToPrint =
new System.Drawing.Printing.PrintDocument();
2.设置打印机开始打印的事件处理函数.函数原形如下：
void docToPrint_PrintPage(object sender,
System.Drawing.Printing.PrintPageEventArgs e)
3.将事件处理函数添加到PrintDocument的PrintPage事件中。
docToPrint.PrintPage+=new PrintPageEventHandler(docToPrint_PrintPage);
4.设置PrintDocument的相关属性，如：
PrintDialog1.AllowSomePages = true;PrintDialog1.ShowHelp = true;
5.把PrintDialog的Document属性设为上面配置好的PrintDocument的实例：
PrintDialog1.Document = docToPrint;
6.调用PrintDialog的ShowDialog函数显示打印对话框：
DialogResult result = PrintDialog1.ShowDialog();
7.根据用户的选择，开始打印：
if (result==DialogResult.OK)
{
docToPrint.Print();
}
8.打印预览控件PrintPreviewDialog
例子如下：
使用时先创建PrintService类的实例，然后调用void StartPrint(Stream streamToPrint,string streamType)函数开始打印。其中streamToPrint是要打印的内容（字节流），streamType是流的类型（txt表示普通文本，image表示图像）；
public partial class PrintTxt
{
private PrintPreviewDialog PrintPreview = new PrintPreviewDialog();
private string StreamType;
private Image image = null;
private Stream StreamToPrint = null;
Font mainFont = new Font("宋体", 12);//打印的字体
public string Filename =null;
//1、实例化打印文档
PrintDocument pdDocument = new PrintDocument();
private string[] lines;
private int linesPrinted;
public PrintTxt(string filepath,string filetype)
{
Filename = Path.GetFileNameWithoutExtension(filepath);
//订阅BeginPrint事件
pdDocument.BeginPrint += new PrintEventHandler(pdDocument_BeginPrint);
//訂閱EndPrint事件，释放资源
pdDocument.PrintPage += new PrintPageEventHandler(OnPrintPage);
//订阅Print打印事件,该方法必须放在订阅打印事件的最后
FileStream fs = new FileStream(filepath, FileMode.Open, FileAccess.Read);
StartPrint(fs, filetype);
//打印结束
pdDocument.EndPrint += new PrintEventHandler(pdDocument_EndPrint);
} //2、启动Print打印方法
public void StartPrint(Stream streamToPrint, string streamType) { //返回值的PageSettings A4\A5 PageSettings ps = new PageSettings(); //显示设置打印页对话框 PageSetupDialog Psdl = new PageSetupDialog(); //打印多份设置，注意，该方法需放在printpage方法后面。 PrintDialog pt = new PrintDialog(); pt.AllowCurrentPage = true; pt.AllowSomePages = true; pt.AllowPrintToFile = true; StreamToPrint = streamToPrint;//打印的字节流 StreamType = streamType; //打印的类型 pdDocument.DocumentName = Filename; //打印的文件名 Psdl.Document = pdDocument; PrintPreview.Document = pdDocument; pt.Document = pdDocument; Psdl.PageSettings = pdDocument.DefaultPageSettings; try { //显示对话框 if (Psdl.ShowDialog() == DialogResult.OK) { ps = Psdl.PageSettings; pdDocument.DefaultPageSettings = Psdl.PageSettings; } if (pt.ShowDialog() == DialogResult.OK) { pdDocument.PrinterSettings.Copies = pt.PrinterSettings.Copies; pdDocument.Print(); } if(PrintPreview.ShowDialog()==DialogResult.OK ) //调用打印 pdDocument.Print(); * PrintDocument对象的Print()方法在PrintController类中执行PrintPage事件。 */ } catch (InvalidPrinterException ex) { MessageBox.Show(ex.Message, "Simple Editor", MessageBoxButtons.OK, MessageBoxIcon.Error); throw; } } /// <summary>
/// 3、得到打印內容 /// 每个打印任务只调用OnBeginPrint()一次。 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> void pdDocument_BeginPrint(object sender, PrintEventArgs e) { char[] param = { '\n' }; char[] trimParam = { '\r' };//回车 switch (StreamType) { case "txt": StringBuilder text = new StringBuilder(); System.IO.StreamReader streamReader = new StreamReader(StreamToPrint, Encoding.Default); while (streamReader.Peek() >= 0) { lines = streamReader.ReadToEnd().Split(param); for (int i = 0; i < lines.Length; i++) { lines[i] = lines[i].TrimEnd(trimParam); } } break; case "image": image = System.Drawing.Image.FromStream(StreamToPrint); break; default: break; } } /// <summary> /// 4、绘制多个打印界面 /// printDocument的PrintPage事件 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void OnPrintPage(object sender, PrintPageEventArgs e) { int leftMargin = Convert.ToInt32((e.MarginBounds.Left) * 3 / 4); //左边距 int topMargin = Convert.ToInt32(e.MarginBounds.Top * 2 / 3); //顶边距 switch (StreamType) { case "txt": while (linesPrinted < lines.Length) { //向画布中填写内容 e.Graphics.DrawString(lines[linesPrinted++], new Font("Arial", 10), Brushes.Black, leftMargin, topMargin, new StringFormat()); topMargin += 55;//行高为55，可调整 //走纸换页 if (topMargin >= e.PageBounds.Height - 60)//页面累加的高度大于页面高度。根据自己需要，可以适当调整 { //如果大于设定的高 e.HasMorePages = true; /* * PrintPageEventArgs类的HaeMorePages属性为True时，通知控件器，必须再次調用OnPrintPage()方法，打印一个页面。 * PrintLoopI()有一个用於每个要打印的页面的序例。如果HasMorePages是False，PrintLoop()就会停止。 */ return; } } break; case "image"://一下涉及剪切图片, int width = image.Width; int height = image.Height; if ((width / e.MarginBounds.Width) > (height / e.MarginBounds.Height)) { width = e.MarginBounds.Width; height = image.Height * e.MarginBounds.Width / image.Width; } else { height = e.MarginBounds.Height; width = image.Width * e.MarginBounds.Height / image.Height; } System.Drawing.Rectangle destRect = new System.Drawing.Rectangle(topMargin, leftMargin, width, height); //向画布写入图片 for (int i = 0; i < Convert.ToInt32(Math.Floor((double)image.Height/ 820)) + 1; i++) { e.Graphics.DrawImage(image, destRect, i*820,i*1170 , image.Width, image.Height, System.Drawing.GraphicsUnit.Pixel); //走纸换页 if (i * 1170 >= e.PageBounds.Height - 60)//页面累加的高度大于页面高度。根据自己需要，可以适当调整 { //如果大于设定的高 e.HasMorePages = true; /* * PrintPageEventArgs类的HaeMorePages属性为True时，通知控件器，必须再次調用OnPrintPage()方法，打印一个页面。 * PrintLoopI()有一个用於每个要打印的页面的序例。如果HasMorePages是False，PrintLoop()就会停止。 */ return; } } break; } //打印完毕后，画线条，且注明打印日期 e.Graphics.DrawLine(new Pen(Color.Black), leftMargin, topMargin, e.MarginBounds.Right, topMargin); string strdatetime = DateTime.Now.ToLongDateString() + DateTime.Now.ToLongTimeString(); e.Graphics.DrawString(string.Format("打印时间：{0}", strdatetime), mainFont, Brushes.Black, e.MarginBounds.Right-240, topMargin+40, new StringFormat()); linesPrinted = 0; //绘制完成后，关闭多页打印功能 e.HasMorePages = false; } /// <summary>
///5、EndPrint事件,释放资源 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> void pdDocument_EndPrint(object sender, PrintEventArgs e) { //变量Lines占用和引用的字符串数组，现在释放 lines = null; } } //PrintTxt simple = new PrintTxt("D:\\Mainsoft\\12.txt", "txt");
