C# 字符流打印类
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using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Windows.Forms; using System.Drawing; using System.Drawing.Printing; using System.IO; using System.Runtime.InteropServices; namespace PrintService { sealed class TextFilePrinter { string sTreamPriStr; Encoding theEncode; Font theFont; StreamReader srToPrint; int currPage; public TextFilePrinter(string sTreamPriStr) : this(sTreamPriStr, Encoding.GetEncoding("utf-8"), new Font("新宋体", 10)) { } public TextFilePrinter(string sTreamPriStr, Encoding theEncode, Font theFont) { this.sTreamPriStr = sTreamPriStr; this.theEncode = theEncode; this.theFont = theFont; } public void Print() { srToPrint = new StreamReader(new MemoryStream(Encoding.UTF8.GetBytes(sTreamPriStr))); PrintDialog dlg = new PrintDialog(); dlg.Document = GetPrintDocument(); dlg.AllowSomePages = true; dlg.AllowPrintToFile = false; if (dlg.ShowDialog() == DialogResult.OK) dlg.Document.Print(); } /// <summary> /// 不需要打印预览直接打印 /// </summary> public void Print2() { srToPrint = new StreamReader(new MemoryStream(Encoding.UTF8.GetBytes(sTreamPriStr))); PrintDialog dlg = new PrintDialog(); dlg.Document = GetPrintDocument(); dlg.AllowSomePages = true; dlg.AllowPrintToFile = false; dlg.Document.Print(); } public void View() { srToPrint = new StreamReader(new MemoryStream(Encoding.UTF8.GetBytes(sTreamPriStr))); PrintPreviewDialog dlg = new PrintPreviewDialog(); dlg.Document = GetPrintDocument(); dlg.ShowDialog(); } PrintDocument GetPrintDocument() { currPage = 1; PrintDocument doc = new PrintDocument(); doc.DocumentName = "打印"; doc.PrintPage += new PrintPageEventHandler(PrintPageEvent); return doc; } void PrintPageEvent(object sender, PrintPageEventArgs ev) { string line = null; float linesPerPage = ev.MarginBounds.Height / theFont.GetHeight(ev.Graphics); bool isSomePages = ev.PageSettings.PrinterSettings.PrintRange == PrintRange.SomePages; if (isSomePages) { while (currPage < ev.PageSettings.PrinterSettings.FromPage) { for (int count = 0; count < linesPerPage; count++) { line = srToPrint.ReadLine(); if (line == null) break; } if (line == null) return; currPage++; } if (currPage > ev.PageSettings.PrinterSettings.ToPage) return; } for (int count = 0; count < linesPerPage; count++) { line = srToPrint.ReadLine(); if (line == null) break; //ev.Graphics.DrawString(line, theFont, Brushes.Black, ev.MarginBounds.Left, // ev.MarginBounds.Top + (count * theFont.GetHeight(ev.Graphics)), new StringFormat()); ev.Graphics.DrawString(line, theFont, Brushes.Black, 2, count * theFont.GetHeight(ev.Graphics) - 1, new StringFormat()); } currPage++; if (isSomePages && currPage > ev.PageSettings.PrinterSettings.ToPage) return; if (line != null) ev.HasMorePages = true; } } public static class PrinterHel { //GetDefaultPrinter用到的API函数说明 [DllImport("winspool.drv", CharSet = CharSet.Auto, SetLastError = true)] internal static extern bool GetDefaultPrinter(StringBuilder pszBuffer, ref int size); //SetDefaultPrinter用到的API函数声明 [DllImport("winspool.drv", CharSet = CharSet.Auto, SetLastError = true)] internal static extern bool SetDefaultPrinter(string Name); #region 获取本地打印机列表 /// <summary> /// 获取本地打印机列表 /// </summary> /// <returns>打印机列表</returns> public static List<string> GetPrinterList() { List<string> printRet = Cprinter.GetLocalPrinter(); return printRet; } #endregion 获取本地打印机列表 #region 获取本机的默认打印机名称 /// <summary> /// 获取本机的默认打印机名称 /// </summary> /// <returns>默认打印机名称</returns> public static string GetDeaultPrinterName() { StringBuilder dp = new StringBuilder(256); int size = dp.Capacity; if (GetDefaultPrinter(dp, ref size)) { return dp.ToString(); } else { return string.Empty; } } #endregion 获取本机的默认打印机名称 #region 设置默认打印机 /// <summary> /// 设置默认打印机 /// </summary> /// <param name="PrinterName">可用的打印机名称</param> public static void SetPrinterToDefault(string PrinterName) { SetDefaultPrinter(PrinterName); } #endregion 设置默认打印机 #region 判断打印机是否在系统可用的打印机列表中 ///// <summary> ///// 判断打印机是否在系统可用的打印机列表中 ///// </summary> ///// <param name="PrinterName">打印机名称</param> ///// <returns>是:在;否:不在</returns> public static bool PrinterInList(string PrinterName) { bool bolRet = false; List<string> alPrinters = GetPrinterList(); for (int i = 0; i < alPrinters.Count; i++) { if (PrinterName == alPrinters[i].ToString()) { bolRet = true; break; } } alPrinters.Clear(); alPrinters = null; return bolRet; } #endregion 判断打印机是否在系统可用的打印机列表中 } }