前两天领导说不用web端的打印插件（C-Lodop），想用C#来实现，让我研究一下调用打印机的方法，就有了这篇总结
.NET Core或.NET 5的话要引用一下NuGet包 System.Drawing.Common
获取打印机列表
PrinterSettings.InstalledPrinters.Cast<string>();
定义打印接口
public interface IPrinter
{
/// <summary>
/// 设置页面大小
/// </summary>
/// <param name="paperWidth"></param>
/// <param name="paperHight"></param>
void SetPageSize(double paperWidth, int? paperHight);
/// <summary>
/// 打印文字
/// </summary>
/// <param name="content"></param>
/// <param name="fontSize"></param>
/// <param name="stringAlignment"></param>
/// <param name="width"></param>
/// <param name="offset"></param>
void PrintText(
string content,
FontSize fontSize = FontSize.Normal,
StringAlignment stringAlignment = StringAlignment.Near,
float width = 1,
float offset = 0
);
/// <summary>
/// 打印图片
/// </summary>
/// <param name="image"></param>
/// <param name="stringAlignment"></param>
void PrintImage(Image image, StringAlignment stringAlignment = StringAlignment.Near);
/// <summary>
/// 打印一行
/// </summary>
void PrintSolidLine();
/// <summary>
/// 打印一行虚线
/// </summary>
/// <param name="fontSize"></param>
void PrintDottedLine();
/// <summary>
/// 新起一行
/// </summary>
void NewLine();
/// <summary>
/// 开始打印
/// </summary>
void Print();
}
打印接口的实现
public class Printer : IPrinter
{
#region fields
private PrintDocument _printDoc = new PrintDocument();
/// <summary>
/// 打印对象打印宽度(根据英寸换算而来,paperWidth * 3.937)
/// </summary>
private int _paperWidth;
private int _paperHight;
private const float _charProportion = 0.7352f;
private const float _lineHeightProportion = 1.6f;
private const string _fontName = "SimHei";
private int _printIndex = 0;
/// <summary>
/// 打印模式：1、自动分页模式 2、连续不分页模式
/// </summary>
private int _mode;
private IList<Action<Graphics>> _printActions = new List<Action<Graphics>>();
/// <summary>
/// 当前的打印高度，当调用换行或者图片打印时会增加此字段值
/// </summary>
private float _currentHeight = 0;
public float NewLineOffset { get; set; } = (int)FontSize.Normal * _lineHeightProportion;
#endregion
#region ctor
/// <summary>
/// 初始化机打印对象
/// </summary>
/// <param name="printerName">打印机名称</param>
/// <param name="paperWidth">打印纸宽度</param>
/// <param name="paperHight">打印纸高度</param>
internal Printer(string printerName)
{
_printDoc.PrinterSettings.PrinterName = printerName;
_printDoc.PrintPage += PrintPageDetails;
//默认为58mm
SetPageSize(58, null);
_printDoc.PrintController = new StandardPrintController();
}
#endregion
#region eventHandler
void PrintPageDetails(object sender, PrintPageEventArgs e)
{
while (_printIndex < _printActions.Count)
{
var originHeight = _currentHeight;
_printActions[_printIndex](e.Graphics);
_printIndex++;
if (_currentHeight > e.PageBounds.Height - 20)
{
if (_mode == 1)
{
_currentHeight = 0;
// HasMorePages 设置为true后，会继续触发PrintPage，因此_printIndex需要在外部进行定义
e.HasMorePages = true;
return;
}
}
}
e.HasMorePages = false;
}
#endregion
#region IPrinterImplement
/// <summary>
/// 设置页面大小
/// </summary>
/// <param name="paperWidth"></param>
/// <param name="paperHight"></param>
public void SetPageSize(double paperWidth, int? paperHight)
{
switch (paperWidth)
{
case 80:
//80打印纸扣去两边内距实际可打的宽度为72.1
paperWidth = 72.1;
break;
case 76:
//76打印纸扣去两边内距实际可打的宽度为63.5
paperWidth = 63.5;
break;
case 58:
//58打印纸扣去两边内距实际可打的宽度为48
paperWidth = 48;
break;
default:
paperWidth = paperWidth - 10;
break;
}
_paperWidth = Convert.ToInt32(Math.Ceiling(paperWidth * 3.937));
_mode = 1;
if (!paperHight.HasValue)
{
paperHight = 297;
_mode = 2; // 设置为连续不分页模式
}
_paperHight = Convert.ToInt32(Math.Ceiling(paperHight.Value * 3.937));
_printDoc.DefaultPageSettings.PaperSize = new PaperSize("", _paperWidth, _paperHight);
}
/// <summary>
/// 开始打印
/// </summary>
public void Print()
{
_printIndex = 0;
_currentHeight = 0;
_printDoc.EndPrint += (_, _) => Console.WriteLine("打印完成！");
if (_mode == 2)
{
// 通过下面的方式计算出实际页面高度
using (Bitmap img = new Bitmap(_paperWidth, _paperHight))
{
var g = Graphics.FromImage(img);
foreach (var item in _printActions)
{
item(g);
}
_paperHight = Convert.ToInt32(Math.Ceiling(_currentHeight)) + 5;
_printDoc.DefaultPageSettings.PaperSize = new PaperSize("", _paperWidth, _paperHight);
_printIndex = 0;
_currentHeight = 0;
}
}
_printDoc.Print();
_printDoc.Dispose();
_printDoc = new PrintDocument();
_printActions.Clear();
}
/// <summary>
/// 新起一行
/// </summary>
public void NewLine()
{
_printActions.Add(g =>
{
_currentHeight += NewLineOffset;
NewLineOffset = (int)FontSize.Normal * _lineHeightProportion;
});
}
/// <summary>
/// 打印文字
/// </summary>
/// <param name="content"></param>
/// <param name="fontSize"></param>
/// <param name="alignment"></param>
/// <param name="width"></param>
/// <param name="offset"></param>
public void PrintText(string content, FontSize fontSize = FontSize.Normal, StringAlignment alignment = StringAlignment.Near, float width = 1, float offset = 0)
{
_printActions.Add(g =>
{
float contentWidth = width == 1 ? _paperWidth * (1 - offset) : width * _paperWidth;
string newContent = ContentWarp(content, fontSize, contentWidth, out var rowNum);
var font = new Font(_fontName, (int)fontSize, FontStyle.Regular);
var point = new PointF(offset * _paperWidth, _currentHeight);
var size = new SizeF(contentWidth, (int)fontSize * _lineHeightProportion * rowNum);
var layoutRectangle = new RectangleF(point, size);
var format = new StringFormat
{
Alignment = alignment,
FormatFlags = StringFormatFlags.NoWrap
};
g.DrawString(newContent, font, Brushes.Black, layoutRectangle, format);
float thisHeightOffset = rowNum * (int)fontSize * _lineHeightProportion;
if (thisHeightOffset > NewLineOffset) NewLineOffset = thisHeightOffset;
});
}
/// <summary>
/// 打印图片
/// </summary>
/// <param name="image"></param>
/// <param name="stringAlignment"></param>
public void PrintImage(Image image, StringAlignment stringAlignment = StringAlignment.Near)
{
_printActions.Add(g =>
{
int x = 0;
switch (stringAlignment)
{
case StringAlignment.Near:
break;
case StringAlignment.Center:
x = (_paperWidth - image.Width) / 2;
break;
case StringAlignment.Far:
x = _paperWidth - image.Width;
break;
default:
break;
}
var point = new Point(x, Convert.ToInt32(_currentHeight));
var size = new Size(image.Width, image.Height);
var rectangle = new Rectangle(point, size);
g.DrawImage(image, rectangle);
NewLineOffset = image.Height;
});
}
/// <summary>
/// 打印一行实线
/// </summary>
public void PrintSolidLine()
{
_printActions.Add(g =>
{
var pen = new Pen(new SolidBrush(Color.Black));
pen.Width = 1f;
g.DrawLine(pen, new Point(0, Convert.ToInt32(Math.Ceiling(_currentHeight))), new Point(_paperWidth, Convert.ToInt32(Math.Ceiling(_currentHeight))));
_currentHeight += 3;
});
}
/// <summary>
/// 打印一行虚线
/// </summary>
public void PrintDottedLine()
{
var fontSize = FontSize.Normal;
int charNum = (int)(_paperWidth / ((int)fontSize * _charProportion));
var builder = new StringBuilder();
for (int i = 0; i < charNum; i++)
{
builder.Append('-');
}
PrintText(builder.ToString(), fontSize, StringAlignment.Center);
}
#endregion
#region methods
/// <summary>
/// 对内容进行分行，并返回行数
/// </summary>
/// <param name="content">内容</param>
/// <param name="fontSize">文字大小</param>
/// <param name="width">内容区宽度</param>
/// <returns>行数</returns>
private static string ContentWarp(string content, FontSize fontSize, float width, out int row)
{
content = content.Replace(Environment.NewLine, string.Empty);
//0.7282 字符比例
var builder = new StringBuilder();
float nowWidth = 0;
row = 1;
foreach (char item in content)
{
int code = Convert.ToInt32(item);
float charWidth = code < 128 ? _charProportion * (int)fontSize : _charProportion * (int)fontSize * 2;
nowWidth += charWidth;
if (nowWidth > width)
{
builder.Append(Environment.NewLine);
nowWidth = charWidth;
row++;
}
builder.Append(item);
}
return builder.ToString();
}
#endregion
}
创建打印机的工厂类
public static class PrinterFactory
{
public static IEnumerable<string> GetAllPrints()
{
return PrinterSettings.InstalledPrinters.Cast<string>();
}
public static Printer GetPrinter(string printerName)
{
if (string.IsNullOrEmpty(printerName)) throw new ArgumentException(nameof(printerName));
return new Printer(printerName);
}
}
使用
static void Main(string[] args)
{
// Microsoft XPS Document Writer 是测试时使用的，实际使用中，要替换成真正的打印机
var printer = PrinterFactory.GetPrinter("Microsoft XPS Document Writer");
printer.SetPageSize(80, null);
printer.NewLine();
var img = GetLogo();
printer.PrintImage(img, StringAlignment.Center);
printer.NewLine();
printer.NewLine();
printer.PrintText("永辉超市", FontSize.Large, alignment: StringAlignment.Center);
printer.NewLine();
printer.NewLine();
printer.PrintText("单号：XD000269");
printer.PrintText("流水号：000269", offset: 0.5f);
printer.NewLine();
printer.PrintText("收银员：***");
printer.PrintText("日期：" + DateTime.Now.ToString("yyyy/MM/dd"), offset: 0.5f);
printer.NewLine();
printer.PrintText("VIP客户卡号：001");
printer.NewLine();
printer.PrintSolidLine();
printer.NewLine();
printer.PrintText("名称");
printer.PrintText("单价", offset: 0.35f);
printer.PrintText("数量", offset: 0.65f);
printer.PrintText("金额", alignment: StringAlignment.Far);
printer.NewLine();
printer.PrintText("芹菜", width: 0.35f);
printer.PrintText("2.9", width: 0.2f, offset: 0.35f);
printer.PrintText("1", width: 0.2f, offset: 0.65F);
printer.PrintText("2.9", alignment: StringAlignment.Far);
printer.NewLine();
printer.PrintDottedLine();
printer.NewLine();
printer.PrintText("合计");
printer.PrintText("1", offset: 0.65f);
printer.PrintText("2.90", alignment: StringAlignment.Far);
printer.NewLine();
printer.PrintText("满0.00减0.00折扣");
printer.PrintText("-0.00", alignment: StringAlignment.Far);
printer.NewLine();
printer.PrintText("优惠金额：2.90");
printer.PrintText("实收金额：0", offset: 0.5f);
printer.NewLine();
printer.PrintText("收款金额：0.00");
printer.PrintText("找零金额：-2.90", offset: 0.5f);
printer.NewLine();
printer.PrintDottedLine();
printer.NewLine();
printer.PrintText("会员卡：001");
printer.NewLine();
printer.PrintText("本次积分：");
printer.PrintText("会员余额：43.87", offset: 0.5f);
printer.NewLine();
printer.PrintText("可用积分：");
printer.NewLine();
printer.PrintSolidLine();
printer.NewLine();
printer.PrintText("永辉超市", FontSize.Large, alignment: StringAlignment.Center);
printer.NewLine();
printer.PrintText("欢迎光临，谢谢惠顾！", FontSize.Large, alignment: StringAlignment.Center);
printer.NewLine();
printer.Print();
GC.Collect();
Console.ReadKey();
}
private static Image GetLogo()
{
var path = Path.Combine(Directory.GetCurrentDirectory(), "logo.jpg");
using (var fileStream = File.OpenRead(path))
{
fileStream.Seek(0, SeekOrigin.Begin);
return Image.FromStream(fileStream);
}
}
效果如下
demo已上传至 github