C#打印相关的知识点

GDI+可以用来创建和处理图像，还可以“绘制文本”。人们通常认为，文本时打印出来的，不是绘制出来的，但是在.NET中，显示和渲染文本的技术类似于显示图形的技术：必须创建Graphics对象，然后利用该对象的方法来定位和渲染文本字符串。所以，字体（Font）是打印的基础知识，有关字体的知识请参阅MSDN  http://msdn.microsoft.com/zh-cn/library/system.drawing.font(v=vs.110).aspx 。

System.Drawing.Printing命名空间的PrintDocument类提供了控制打印进程的方法、成员属性和事件，因此，要建立输出到打印机的程序，就首先要建立PrintDocument对象。

PrintDocument pDocument = new PrintDocument();

然后调用PrintDocument.Print方法启动打印进程，此时触发PrintDocument类的BeginPrint和PrintPage事件，PrintPage事件处理方法包含生成输出的逻辑和语句，包括确定打印行数、输出DrawString语句、负责通知底层的打印控制器是否还有待打印的页面（设置HasMorePages属性）等。触发流程如下：

private void FrmMain_Load(object sender, EventArgs e)
{
sr = new StreamReader(@"数据的路径(.txt)");
//数据格式如下
/*
1000758,1050,SKJALDHAHDLKJAH,125.470
1000758,1050,SKJALDHAHDLKJAH,125.470
1000758,1050,SKJALDHAHDLKJAH,125.470
1000758,1050,SKJALDHAHDLKJAH,125.470
1000758,1050,SKJALDHAHDLKJAH,125.470
1000758,1050,SKJALDHAHDLKJAH,125.470
1000758,1050,SKJALDHAHDLKJAH,125.470
1000758,1050,SKJALDHAHDLKJAH,125.470
1000758,1050,SKJALDHAHDLKJAH,125.470
1000758,1050,SKJALDHAHDLKJAH,125.470
*/
}

加载数据

1         StreamReader sr;
2         string[] prtLine;
3         Font rptFont;
4         Font hdrFont;
5         string title = "Title";
6         float lineHeight;

类级别的变量

  private void pDocument_BeginPrint(object sender, PrintEventArgs e)
        {
            rptFont = new Font("Arial", 10);
            hdrFont = new Font(rptFont, FontStyle.Bold);
        }

BeginPrint事件，一般用于初始化字体等变量

 private void pDocument_EndPrint(object sender, PrintEventArgs e)
        {
           rptFont.Dispose();
           hdrFont.Dispose();
           sr.Close();
        }

EndPrint事件，一般用于释放资源，关闭数据连接等

 private void pDocument_PrintPage(object sender, PrintPageEventArgs e)
        {
            Graphics graphics = e.Graphics;
            int xPos = e.MarginBounds.Left;
            int lineCt = 0;
            lineHeight = hdrFont.GetHeight(graphics);
            int linesPerPage = (int)((e.MarginBounds.Bottom - e.MarginBounds.Top) / lineHeight - 2);
            float yPos = 2 * lineHeight + e.MarginBounds.Top;
            int hdrPos = e.MarginBounds.Top;
            PrintHdr(graphics, hdrPos, 200);
            string prod;
            char[] delim = { ‘,‘ };
            while ((prod = sr.ReadLine()) != null)
            {
                prtLine = prod.Split(delim, 4);
                yPos += lineHeight;
                PrintDetail(graphics, yPos);
                if (lineCt == linesPerPage)
                {
                    e.HasMorePages = true;
                    lineCt = 0;
                    break;
                }
                lineCt++;
            }
        }

PrintPages事件，包括主要的打印逻辑以及HasMorePages属性的设置

 private void PrintHdr(Graphics g, int yPos, int xPos)
        {
            g.DrawString(title, hdrFont, Brushes.Black, xPos, yPos);
            float[] ts = { 80, 80, 200 };
            StringFormat strFmt = new StringFormat();
            strFmt.SetTabStops(0, ts);
            g.DrawString("Code\tVender\tDescription\tCost", hdrFont, Brushes.Black, xPos, yPos + 2 * lineHeight, strFmt);
        }

打印大标题和列标题

 private void PrintDetail(Graphics g, float yPos)
        {
            int xPos = 200;
            StringFormat strFmt = new StringFormat();
            strFmt.Trimming = StringTrimming.EllipsisCharacter;
            strFmt.FormatFlags = StringFormatFlags.NoWrap;
            RectangleF r = new RectangleF(xPos + 160, yPos, 200, lineHeight);
            string invenid = prtLine[0];
            string vendor = prtLine[1];
            string desc = prtLine[2];
            Decimal price = decimal.Parse(prtLine[3]);
            g.DrawString(invenid, rptFont, Brushes.Black, xPos, yPos);
            g.DrawString(vendor, rptFont, Brushes.Black, xPos + 80, yPos);
            g.DrawString(desc, rptFont, Brushes.Black, r, strFmt);
            strFmt.Alignment = StringAlignment.Far;
            strFmt.Trimming = StringTrimming.None;
            g.DrawString(price.ToString("#,###.00"), rptFont, Brushes.Black, xPos + 400, yPos, strFmt);
        }

打印详细内容

 private void btnPrint_Click(object sender, EventArgs e)
        {
            PrintDocument pDocument = new PrintDocument();
            PrintDialog pDialog = new PrintDialog();
            pDialog.Document = pDocument;
            pDialog.AllowSomePages = true;

            PrintPreviewDialog preDialog = new PrintPreviewDialog();
            preDialog.Document = pDocument;
            pDocument.PrintPage += new PrintPageEventHandler(pDocument_PrintPage);
            pDocument.BeginPrint += new PrintEventHandler(pDocument_BeginPrint);
            pDocument.EndPrint += new PrintEventHandler(pDocument_EndPrint);
            if (pDialog.ShowDialog() == DialogResult.OK)
            {
                pDocument.Print();
            }
        }

按钮事件