.NET (Core and Framework)

Martin Beukes wrote:

I need use the paint event of a control to retun an image of that control.

////////////////////////////////////////////////////////////////////////////////////////////////
//
//	CopyRight 2009, www.perceler.com, Luc Pattyn
//
//	Version 1.0
//
//	use freely for non-commercial use as long as this notice remains present;
//	ask me before using commercially.
//
////////////////////////////////////////////////////////////////////////////////////////////////

using System;
using System.Windows.Forms;
using System.Drawing;
using System.Runtime.InteropServices;
using System.Drawing.Printing;

namespace LP_Core {

	/// <summary>
	/// LP_RichTextBox is an extended RichTextBox offering Print functionality (courtesy Microsoft)
	/// and a proprietary method to draw all the content to a bitmap
	/// </summary>
	/// <remarks>"http://support.microsoft.com/kb/812425"</remarks>
	[System.ComponentModel.DesignerCategory("Code")]
	class LP_RichTextBox : RichTextBox {
		//Convert the unit used by the .NET framework (1/100 inch) 
		//and the unit used by Win32 API calls (twips 1/1440 inch)
		private const double anInch = 14.4;

		[StructLayout(LayoutKind.Sequential)]
		private struct RECT {
			public int Left;
			public int Top;
			public int Right;
			public int Bottom;
		}

		[StructLayout(LayoutKind.Sequential)]
		private struct CHARRANGE {
			public int cpMin;         //First character of range (0 for start of doc)
			public int cpMax;           //Last character of range (-1 for end of doc)
		}

		[StructLayout(LayoutKind.Sequential)]
		private struct FORMATRANGE {
			public IntPtr hdc;             //Actual DC to draw on
			public IntPtr hdcTarget;       //Target DC for determining text formatting
			public RECT rc;                //Region of the DC to draw to (in twips)
			public RECT rcPage;            //Region of the whole DC (page size) (in twips)
			public CHARRANGE chrg;         //Range of text to draw (see earlier declaration)
		}

		private const int WM_USER  = 0x0400;
		private const int EM_FORMATRANGE  = WM_USER + 57;

		[DllImport("USER32.dll")]
		private static extern IntPtr SendMessage(IntPtr hWnd, int msg, IntPtr wp, IntPtr lp);

		// Render the contents of the RichTextBox for printing
		//	Return the last character printed + 1 (printing start from this point for next page)
		// WARNING: I have not tested this method, I only used it as a starting point
		//	to create the next method!
		public int Print(int charFrom, int charTo, PrintPageEventArgs e) {
			//Calculate the area to render and print
			RECT rectToPrint;
			rectToPrint.Top = (int)(e.MarginBounds.Top * anInch);
			rectToPrint.Bottom = (int)(e.MarginBounds.Bottom * anInch);
			rectToPrint.Left = (int)(e.MarginBounds.Left * anInch);
			rectToPrint.Right = (int)(e.MarginBounds.Right * anInch);

			//Calculate the size of the page
			RECT rectPage;
			rectPage.Top = (int)(e.PageBounds.Top * anInch);
			rectPage.Bottom = (int)(e.PageBounds.Bottom * anInch);
			rectPage.Left = (int)(e.PageBounds.Left * anInch);
			rectPage.Right = (int)(e.PageBounds.Right * anInch);

			IntPtr hdc = e.Graphics.GetHdc();

			FORMATRANGE fmtRange;
			fmtRange.chrg.cpMax = charTo;		//Indicate character from to character to 
			fmtRange.chrg.cpMin = charFrom;
			fmtRange.hdc = hdc;                    //Use the same DC for measuring and rendering
			fmtRange.hdcTarget = hdc;              //Point at printer hDC
			fmtRange.rc = rectToPrint;             //Indicate the area on page to print
			fmtRange.rcPage = rectPage;            //Indicate size of page

			IntPtr res = IntPtr.Zero;

			IntPtr wparam = IntPtr.Zero;
			wparam = new IntPtr(1);

			//Get the pointer to the FORMATRANGE structure in memory
			IntPtr lparam= IntPtr.Zero;
			lparam = Marshal.AllocCoTaskMem(Marshal.SizeOf(fmtRange));
			Marshal.StructureToPtr(fmtRange, lparam, false);

			//Send the rendered data for printing 
			res = SendMessage(Handle, EM_FORMATRANGE, wparam, lparam);

			//Free the block of memory allocated
			Marshal.FreeCoTaskMem(lparam);

			//Release the device context handle obtained by a previous call
			e.Graphics.ReleaseHdc(hdc);

			//Return last + 1 character printer
			return res.ToInt32();
		}

		public void DrawToBitmap(Bitmap bitmap) {
			//Calculate the area to render and print
			RECT rectToPrint;
			rectToPrint.Top = 0;
			rectToPrint.Bottom = (int)(bitmap.Height*anInch);
			rectToPrint.Left = 0;
			rectToPrint.Right = (int)(bitmap.Width*anInch);

			//Calculate the size of the page
			RECT rectPage;
			rectPage.Top = 0;
			rectPage.Bottom = (int)(bitmap.Height*anInch);
			rectPage.Left = 0;
			rectPage.Right = (int)(bitmap.Width*anInch);

			Graphics g=Graphics.FromImage(bitmap);
			IntPtr hdc = g.GetHdc();

			FORMATRANGE fmtRange;
			// [0,-1]=everything
			fmtRange.chrg.cpMax = -1;		//Indicate character from to character to 
			fmtRange.chrg.cpMin = 0;
			fmtRange.hdc = hdc;                    //Use the same DC for measuring and rendering
			fmtRange.hdcTarget = hdc;              //Point at printer hDC
			fmtRange.rc = rectToPrint;             //Indicate the area on page to print
			fmtRange.rcPage = rectPage;            //Indicate size of page

			IntPtr res = IntPtr.Zero;

			IntPtr wparam = IntPtr.Zero;
			wparam = new IntPtr(1);

			//Get the pointer to the FORMATRANGE structure in memory
			IntPtr lparam= IntPtr.Zero;
			lparam = Marshal.AllocCoTaskMem(Marshal.SizeOf(fmtRange));
			Marshal.StructureToPtr(fmtRange, lparam, false);

			//Send the rendered data for printing 
			res = SendMessage(Handle, EM_FORMATRANGE, wparam, lparam);

			//Free the block of memory allocated
			Marshal.FreeCoTaskMem(lparam);

			//Release the device context handle obtained by a previous call
			g.ReleaseHdc(hdc);

		}
	}
}

private void Control_Paint(object sender, PaintEventArgs e)
{
    Control control = sender as Control;
    if (control != null)
    {
        using(MemoryStream memoryStream = new MemoryStream())
        using (Bitmap bitmap = new Bitmap(memoryStream))
        {
            control.DrawToBitmap(bitmap, control.Bounds);
            // bitmap is now in memoryStream
        }
    }
}

sitruc7 wrote:

Is activex the only viable solution here or is there something else that can be done?

I are Troll

Thomas O'Donoghue wrote:

While Im not experienced in VB.net I have a team that is

Server:
using System;
using System.Collections;
using System.Collections.Generic;
using System.Text;
using System.IO;
using System.Net;
using System.Net.Sockets;
using System.Runtime.Serialization.Formatters.Binary;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            IPEndPoint ip = new IPEndPoint(IPAddress.Any, 9999);
            Socket s = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);

            s.Bind(ip);
            s.Listen(10);
            Console.WriteLine("Waiting for a client...");
            Socket cli = s.Accept();
            IPEndPoint cliep = (IPEndPoint)cli.RemoteEndPoint;
            Console.WriteLine("Connected with {0} at port {1}", cliep.Address, cliep.Port);

            byte[] buffer = new byte[1024];
            cli.Receive(buffer);
            string fname = Encoding.ASCII.GetString(buffer);

            Console.WriteLine("filename is " + fname);
            Console.ReadLine();
                       
            cli.Receive(buffer);
            Object obj = new Object();
            obj = bytearraytoobject(buffer);

            ArrayList al = (ArrayList)obj;
            int i = 0;
            foreach (Object o in al)
            {
                Console.WriteLine("\t[{0}]:\t{1}", i++, o);
            }
            Console.WriteLine();

            ArrayList qal=new ArrayList();
            Random rnd = new Random(DateTime.Now.Millisecond);
            for (int counter = 0; counter < 5; counter++)
            {
                int randomindex = rnd.Next(al.Count);
                Console.WriteLine("{0}:{1}", counter+ 1, al[randomindex]);
                qal.Add(al[randomindex]);
            }

            foreach (Object o in qal)
            {
                Console.WriteLine("\t[{0}]:\t{1}", i++, o);
            }

            Object ob = (Object)qal;            
            buffer = objecttobytearray(ob);
            cli.Send(buffer);
            
            Console.ReadLine();

        }
        static Object bytearraytoobject(byte[] buffer)
        {
            MemoryStream ms = new MemoryStream();
            BinaryFormatter bf = new BinaryFormatter();
            ms.Write(buffer, 0, buffer.Length);
            ms.Seek(0, SeekOrigin.Begin);
            Object obj = (Object)bf.Deserialize(ms);
            return obj;
        }
        static byte[] objecttobytearray(Object obj)
        {
            if (obj == null)
                return null;
            BinaryFormatter bf = new BinaryFormatter();
            MemoryStream ms = new MemoryStream();
            bf.Serialize(ms, obj);
            return ms.ToArray();
        }

    }
}

client:
using System;
using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Text;
using System.Net;
using System.Net.Sockets;
using System.Runtime.Serialization.Formatters.Binary;

namespace ConsoleApplication2
{
    class Program
    {
        static void Main(string[] args)
        {
            IPEndPoint ip = new IPEndPoint(IPAddress.Parse("127.0.0.1"), 9999);

            Socket s = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
            try
            {
                s.Connect(ip);
            }
            catch (SocketException e)
            {
                Console.WriteLine("Unable to connect to server" + e);
                return;
            }

            Console.WriteLine("Enter the input file ");
            string inp = Console.ReadLine();

            s.Send(Encoding.ASCII.GetBytes(inp));

            StreamReader sr = new StreamReader(@"c:\" + inp);
            ArrayList al = new ArrayList();

            while (!sr.EndOfStream)
            {
                al.Add(sr.ReadLine());
            }

            Object o = (Object)al;
            byte[] buffer = new byte[1024];
            buffer = objecttobytearray(o);
            s.Send(buffer);

            byte[] buf = new byte[1024];
            Object obj = new Object();
            s.Receive(buf);                        
            obj = bytearraytoobject(buf);
            ArrayList qal = (ArrayList)obj;

            int i = 1;
            foreach (Object ob in qal)
            {
                Console.WriteLine("\t[{0}]:\t{1}", i++, ob);
            }
            Console.WriteLine();

            Console.ReadLine();

        }
        static byte[] objecttobytearray(Object obj)
        {
            if (obj == null)
                return null;
            BinaryFormatter bf = new BinaryFormatter();
            MemoryStream ms = new MemoryStream();
            bf.Serialize(ms, obj);
            return ms.ToArray();
        }
        static Object bytearraytoobject(byte[] buffer)
        {
            MemoryStream ms = new MemoryStream();
            BinaryFormatter bf = new BinaryFormatter();
            ms.Write(buffer, 0, buffer.Length);
            ms.Seek(0, SeekOrigin.Begin);
            Object obj = (Object)bf.Deserialize(ms);
            return obj;
        }
    }
}

peterdrozd wrote:

I could not figure out how to change the background color though.

Ajakblackgoat wrote:

I've tried using RichTextBox but when the text in it becomes large, it becomes noticeably slow to update the text.

I are Troll