printablelistview.cs

Some time during my development works I had the need of printing the contents of a ListView control.

using System;
using System.Collections;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Windows.Forms;
using System.Drawing.Printing;
using System.Drawing.Drawing2D;

namespace PrintableListView
{
	/// <summary>
	///		Summary description for PrintableListView.
	/// </summary>
	public class PrintableListView : System.Windows.Forms.ListView
	{
		// Print fields
		private PrintDocument      m_printDoc   = new PrintDocument();
		private PageSetupDialog    m_setupDlg   = new PageSetupDialog();
		private PrintPreviewDialog m_previewDlg = new PrintPreviewDialog();
		private PrintDialog        m_printDlg   = new PrintDialog();

		private int m_nPageNumber=1;
		private int m_nStartRow=0;
		private int m_nStartCol=0;

		private bool m_bPrintSel=false;

		private bool m_bFitToPage=false;

		private float m_fListWidth=0.0f;
		private float[] m_arColsWidth;

		private float m_fDpi=96.0f;

		private string m_strTitle="";

		/// <summary>
		/// Required designer variable.
		/// </summary>
		private System.ComponentModel.Container components = null;

		#region Properties
		/// <summary>
		///		Gets or sets whether to fit the list width on a single page
		/// </summary>
		/// <value>
		///		<c>True</c> if you want to scale the list width so it will fit on a single page.
		/// </value>
		/// <remarks>
		///		If you choose false (the default value), and the list width exceeds the page width, the list
		///		will be broken in multiple page.
		/// </remarks>
		public bool FitToPage
		{
			get {return m_bFitToPage;}
			set {m_bFitToPage=value;}
		}

		/// <summary>
		///		Gets or sets the title to dispaly as page header in the printed list
		/// </summary>
		/// <value>
		///		A <see cref="string"/> the represents the title printed as page header.
		/// </value>
		public string Title
		{
			get {return m_strTitle;}
			set {m_strTitle=value;}
		}
		#endregion

		public PrintableListView()
		{
			// This call is required by the Windows.Forms Form Designer.
			InitializeComponent();

			m_printDoc.BeginPrint += new PrintEventHandler(OnBeginPrint);
			m_printDoc.PrintPage += new PrintPageEventHandler(OnPrintPage);

			m_setupDlg.Document   = m_printDoc;
			m_previewDlg.Document = m_printDoc;
			m_printDlg.Document   = m_printDoc;

			m_printDlg.AllowSomePages = false;
		}

		/// <summary>
		/// Clean up any resources being used.
		/// </summary>
		protected override void Dispose( bool disposing )
		{
			if( disposing )
			{
				if( components != null )
					components.Dispose();
			}
			base.Dispose( disposing );
		}

		#region Component Designer generated code
		/// <summary>
		/// Required method for Designer support - do not modify 
		/// the contents of this method with the code editor.
		/// </summary>
		private void InitializeComponent()
		{
			components = new System.ComponentModel.Container();
		}
		#endregion

		/// <summary>
		///		Show the standard page setup dialog box that lets the user specify
		///		margins, page orientation, page sources, and paper sizes.
		/// </summary>
		public void PageSetup()
		{
			m_setupDlg.ShowDialog();
		}

		/// <summary>
		///		Show the standard print preview dialog box.
		/// </summary>
		public void PrintPreview()
		{
			m_printDoc.DocumentName = "List View";

			m_nPageNumber = 1;
			m_bPrintSel	  = false;

			m_previewDlg.ShowDialog(this);
		}

		/// <summary>
		///		Start the print process.
		/// </summary>
		public void Print()
		{
			m_printDlg.AllowSelection = this.SelectedItems.Count>0;

			// Show the standard print dialog box, that lets the user select a printer
			// and change the settings for that printer.
			if (m_printDlg.ShowDialog(this) == DialogResult.OK)
			{
				m_printDoc.DocumentName = m_strTitle;

				m_bPrintSel = m_printDlg.PrinterSettings.PrintRange==PrintRange.Selection;

				m_nPageNumber = 1;

				// Start print
				m_printDoc.Print();
			}
		}

		#region Events Handlers
		private void OnBeginPrint(object sender, PrintEventArgs e)
		{
			PreparePrint();
		}

		private void OnPrintPage(object sender, PrintPageEventArgs e)
		{
			int nNumItems = GetItemsCount();  // Number of items to print

			if (nNumItems==0 || m_nStartRow>=nNumItems)
			{
				e.HasMorePages = false;
				return;
			}

			int nNextStartCol = 0; 			  // First column exeeding the page width
			float x = 0.0f;					  // Current horizontal coordinate
			float y = 0.0f;					  // Current vertical coordinate
			float cx = 4.0f;                  // The horizontal space, in hundredths of an inch,
			// of the padding between items text and
			// their cell boundaries.
			float fScale = 1.0f;              // Scale factor when fit to page is enabled
			float fRowHeight = 0.0f;		  // The height of the current row
			float fColWidth  = 0.0f;		  // The width of the current column

			RectangleF rectFull;			  // The full available space
			RectangleF rectBody;			  // Area for the list items

			bool bUnprintable = false;

			Graphics g = e.Graphics;

			if (g.VisibleClipBounds.X<0)	// Print preview
			{
				rectFull = e.MarginBounds;

				// Convert to hundredths of an inch
				rectFull = new RectangleF(rectFull.X/m_fDpi*100.0f,
					rectFull.Y/m_fDpi*100.0f,
					rectFull.Width/m_fDpi*100.0f,
					rectFull.Height/m_fDpi*100.0f);
			}
			else							// Print
			{
				// Printable area (approximately) of the page, taking into account the user margins
				rectFull = new RectangleF(
					e.MarginBounds.Left - (e.PageBounds.Width  - g.VisibleClipBounds.Width)/2,
					e.MarginBounds.Top  - (e.PageBounds.Height - g.VisibleClipBounds.Height)/2,
					e.MarginBounds.Width,
					e.MarginBounds.Height);
			}

			rectBody = RectangleF.Inflate(rectFull, 0, -2*Font.GetHeight(g));

			// Display title at top
			StringFormat sfmt = new StringFormat();
			sfmt.Alignment = StringAlignment.Center;
			g.DrawString(m_strTitle, Font, Brushes.Black, rectFull, sfmt);

			// Display page number at bottom
			sfmt.LineAlignment = StringAlignment.Far;
			g.DrawString("Page " + m_nPageNumber, Font, Brushes.Black, rectFull, sfmt);

			if (m_nStartCol==0 && m_bFitToPage && m_fListWidth>rectBody.Width)
			{
				// Calculate scale factor
				fScale = rectBody.Width / m_fListWidth;
			}

			// Scale the printable area
			rectFull = new RectangleF(rectFull.X/fScale, 
									rectFull.Y/fScale,
									rectFull.Width/fScale, 
									rectFull.Height/fScale);

			rectBody = new RectangleF(rectBody.X/fScale, 
									  rectBody.Y/fScale,
									  rectBody.Width/fScale, 
									  rectBody.Height/fScale);

			// Setting scale factor and unit of measure
			g.ScaleTransform(fScale, fScale);
			g.PageUnit = GraphicsUnit.Inch;
			g.PageScale = 0.01f;

			// Start print
			nNextStartCol=0;
			y = rectBody.Top;

			// Columns headers ----------------------------------------
			Brush brushHeader = new SolidBrush(Color.LightGray);
			Font fontHeader = new Font(this.Font, FontStyle.Bold);
			fRowHeight = fontHeader.GetHeight(g)*3.0f;
			x = rectBody.Left;

			for (int i=m_nStartCol; i<Columns.Count; i++)
			{
				ColumnHeader ch = Columns[i];
				fColWidth = m_arColsWidth[i];

				if ( (x + fColWidth) <= rectBody.Right)
				{
					// Rectangle
					g.FillRectangle(brushHeader, x, y, fColWidth, fRowHeight);
					g.DrawRectangle(Pens.Black, x, y, fColWidth, fRowHeight);

					// Text
					StringFormat sf = new StringFormat();
					if (ch.TextAlign == HorizontalAlignment.Left)
						sf.Alignment = StringAlignment.Near;
					else if (ch.TextAlign == HorizontalAlignment.Center)
						sf.Alignment = StringAlignment.Center;
					else
						sf.Alignment = StringAlignment.Far;

					sf.LineAlignment = StringAlignment.Center;
					sf.FormatFlags = StringFormatFlags.NoWrap;
					sf.Trimming = StringTrimming.EllipsisCharacter;

					RectangleF rectText = new RectangleF(x+cx, y, fColWidth-1-2*cx, fRowHeight);
					g.DrawString(ch.Text, fontHeader, Brushes.Black, rectText, sf);
					x += fColWidth;
				}
				else
				{
					if (i==m_nStartCol)
						bUnprintable=true;

					nNextStartCol=i;
					break;
				}
			}
			y += fRowHeight;

			// Rows ---------------------------------------------------
			int nRow = m_nStartRow;
			bool bEndOfPage = false;
			while (!bEndOfPage && nRow<nNumItems)
			{
				ListViewItem item = GetItem(nRow);

				fRowHeight = item.Bounds.Height/m_fDpi*100.0f + 5.0f;

				if (y+fRowHeight>rectBody.Bottom)
				{
					bEndOfPage=true;
				}
				else
				{
					x = rectBody.Left;

					for (int i=m_nStartCol; i<Columns.Count; i++)
					{
						ColumnHeader ch = Columns[i];
						fColWidth = m_arColsWidth[i];

						if ( (x + fColWidth) <= rectBody.Right)
						{
							// Rectangle
							g.DrawRectangle(Pens.Black, x, y, fColWidth, fRowHeight);

							// Text
							StringFormat sf = new StringFormat();
							if (ch.TextAlign == HorizontalAlignment.Left)
								sf.Alignment = StringAlignment.Near;
							else if (ch.TextAlign == HorizontalAlignment.Center)
								sf.Alignment = StringAlignment.Center;
							else
								sf.Alignment = StringAlignment.Far;

							sf.LineAlignment = StringAlignment.Center;
							sf.FormatFlags = StringFormatFlags.NoWrap;
							sf.Trimming = StringTrimming.EllipsisCharacter;

							// Text
							string strText = i==0 ? item.Text : item.SubItems[i].Text;
							Font font = i==0 ? item.Font : item.SubItems[i].Font;

							RectangleF rectText = new RectangleF(x+cx, y, fColWidth-1-2*cx, fRowHeight);
							g.DrawString(strText, font, Brushes.Black, rectText, sf);
							x += fColWidth;
						}
						else
						{
							nNextStartCol=i;
							break;
						}
					}

					y += fRowHeight;
					nRow++;
				}
			}

			if (nNextStartCol==0)
				m_nStartRow = nRow;

			m_nStartCol = nNextStartCol;

			m_nPageNumber++;

			e.HasMorePages = (!bUnprintable && (m_nStartRow>0 && m_nStartRow<nNumItems) || m_nStartCol>0);

			if (!e.HasMorePages)
			{
				m_nPageNumber=1;
				m_nStartRow=0;
				m_nStartCol=0;
			}

			brushHeader.Dispose();
		}
		#endregion

		private int GetItemsCount()
		{
			return m_bPrintSel ? SelectedItems.Count : Items.Count;
		}

		private ListViewItem GetItem(int index)
		{
			return m_bPrintSel ? SelectedItems[index] : Items[index];
		}

		private void PreparePrint()
		{
			// Gets the list width and the columns width in units of hundredths of an inch.
			this.m_fListWidth = 0.0f;
			this.m_arColsWidth = new float[this.Columns.Count];

			Graphics g = CreateGraphics();
			m_fDpi = g.DpiX;
			g.Dispose();

			for (int i=0; i<Columns.Count; i++)
			{
				ColumnHeader ch = Columns[i];
				float fWidth = ch.Width/m_fDpi*100 + 1; // Column width + separator
				m_fListWidth += fWidth;
				m_arColsWidth[i] = fWidth;
			}
			m_fListWidth += 1; // separator
		}

	}
}