C#

using System;
using System.ComponentModel;
using System.Drawing;
using System.Drawing.Printing;
using System.IO;
using System.Windows.Forms;

namespace TestPrint
{
	/// <summary>
	/// Summary description for Class1.
	/// </summary>
	public class PrintingExample 
	{
		private Font printFont;

		public PrintingExample() 
		{
			Printing();
		}

		public void Printing()
		{
			try 
			{
				PrintDocument pd = new PrintDocument();

				// font-height = 0.78 inchs = 78 hundredths of inch?
				printFont = new Font("Arial", 0.78f,System.Drawing.GraphicsUnit.Inch);

				//The width and height of pagper, in hundredths of inch.
				pd.DefaultPageSettings.PaperSize= new PaperSize("MP", 826, 468);

				//The left, right, top, bottom margin, in hundredths of inch.
				pd.DefaultPageSettings.Margins = new Margins (78,78,78,78);
				/*
				 * pageheight=468-78-78 = 312.
				 * Wanted: print 4 lines per page: 4 = 312/78
				 * If not, how can I...
				 * 
				 */

				pd.PrintPage += new PrintPageEventHandler(pd_PrintPage);
				// Print the document.
				pd.Print();
			} 
			finally 
			{
			}
		} 
  
		// The PrintPage event is raised for each page to be printed.
		private void pd_PrintPage(object sender, PrintPageEventArgs ev) 
		{
			float linesPerPage = 0;
			float yPos =  0;
			int count = 0;
			float leftMargin = ev.MarginBounds.Left;
			float topMargin = ev.MarginBounds.Top;
			float fontHeight = printFont.GetHeight(ev.Graphics);
            
			// Calculate the number of lines per page.
			linesPerPage = ev.MarginBounds.Height  / fontHeight;

			System.Console.Out.Write("MarginBounds.Height: " + ev.MarginBounds.Height.ToString() + "\n");
			System.Console.Out.Write("Font Height        : " + fontHeight.ToString() + "\n");
			System.Console.Out.Write("Line(s) per Page   : " + linesPerPage.ToString() + "\n\n");
			/*
			 * Expected:
			 * MarginBounds.Height: 312
			 * Font Height        : 78
			 * Line(s) per Page   : 4
			 * 
			 * On my computer, it print out:
			 * 
			 * MarginBounds.Height: 312
			 * Font Height        : 89.69238
			 * Line(s) per Page   : 3.478556
			 * 
			 * Press any key to continue
			 * 
			 * You known, I want to set the fontHeight to 78, because of MarginBounds.Height = 312.
			 * 
			 */

			// Iterate over the file, printing each line.
			while (count < linesPerPage && count < 4) 
			{
				string s = count.ToString() + ":" + fontHeight.ToString() + "/" + ev.MarginBounds.Height.ToString();

				yPos = topMargin + (count * fontHeight);

				ev.Graphics.DrawString (s, printFont, Brushes.Black, leftMargin, yPos, new StringFormat());
				// Draw a line to
				ev.Graphics.DrawLine(new Pen(System.Drawing.Color.Black),leftMargin,yPos,leftMargin+400,yPos);

				count++;
			}

			yPos = topMargin + (count * printFont.GetHeight(ev.Graphics));
			ev.Graphics.DrawLine(new Pen(System.Drawing.Color.Black),leftMargin,yPos,leftMargin+400,yPos);
		}

		// This is the main entry point for the application.
		public static void Main(string[] args) 
		{
			new PrintingExample();
		}
	}
}