DirectX draw triangle

This is an example of how to draw a simple triangle using DirectX:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using Microsoft.DirectX;
using Microsoft.DirectX.Direct3D;

namespace DirectXHelloWorld
{
    public partial class DirectXHelloWorld : Form
    {
        //Define device to write to.
        Device device = null;
        // Define a vertexBuffer to store the 3d objects.
        VertexBuffer vertexBuffer = null;

        //Main method.
        static void Main()
        {
            // Instantiate form, initialize graphics and show the form.
            DirectXHelloWorld form = new DirectXHelloWorld();
            form.InitializeGraphics();
            form.Show();

            // Render loop
            while (form.Created)
            {
                form.render();
                Application.DoEvents();
            }
        }
        // Called to draw screen.
        public void render()
        {
            //Clear the backbuffer to a blue color (ARGB = 000000ff)
            device.Clear(ClearFlags.Target, System.Drawing.Color.Black, 1.0f, 0);

            device.BeginScene();

            device.SetStreamSource(0, vertexBuffer, 0);
            device.VertexFormat = CustomVertex.TransformedColored.Format;
            device.DrawPrimitives(PrimitiveType.TriangleList, 0, 1);

            //End the scene
            device.EndScene();
            device.Present();
        }
        // Initalize the graphics system.
        public void InitializeGraphics()
        {
            try
            {
                PresentParameters presentParams = new PresentParameters();
                presentParams.Windowed = true;
                presentParams.SwapEffect = SwapEffect.Discard;

                // On my chepo laptop I don't have  hardward support so I'm
                // using SoftwareVertexProcessing. If you have a real graphics
                // card you should change this to HardwareVertexProcessing.
                device = new Device(0,
                      DeviceType.Hardware,
                      this,
                      CreateFlags.SoftwareVertexProcessing,
                      presentParams);
                device.DeviceReset+=
                       new System.EventHandler(this.OnResetDevice);
                OnResetDevice(device, null);

            }
            catch (DirectXException e)
            {

                MessageBox.Show(null, "Error intializing graphics: " + e.Message, "Error");
                Close();
            }
        }
            public void OnResetDevice(object sender, EventArgs e)
            {
                Device dev = (Device)sender;
                vertexBuffer = new VertexBuffer(typeof(CustomVertex.TransformedColored),3, dev,
                0,
                CustomVertex.TransformedColored.Format,
                Pool.Default);

                GraphicsStream stm = vertexBuffer.Lock(0, 0, 0);
                CustomVertex.TransformedColored[] verts =  new CustomVertex.TransformedColored[3];

                verts[0].X = 150;
                verts[0].Y = 50;
                verts[0].Z = 0.5f;
                verts[0].Rhw = 1;
                verts[0].Color = System.Drawing.Color.Red.ToArgb();
                verts[1].X = 250;
                verts[1].Y = 250;
                verts[1].Z = 0.5f;
                verts[1].Rhw = 1;
                verts[1].Color = System.Drawing.Color.Green.ToArgb();
                verts[2].X = 50;
                verts[2].Y = 250;
                verts[2].Z = 0.5f;
                verts[2].Rhw = 1;
                verts[2].Color = System.Drawing.Color.Blue.ToArgb();
                stm.Write(verts);
                vertexBuffer.Unlock();
            }

    }

}

For more information on DirectX with c# I recommend the following book: <a href="http://www.amazon.com/gp/product/1568812361?ie=UTF8&tag=develoresour-20&linkCode=as2&camp=1789&creative=9325&creativeASIN=1568812361">C# and Game Programming: A Beginner's Guide, Second Edition (Book & CD-ROM)</a><img src="http://www.assoc-amazon.com/e/ir?t=develoresour-20&l=as2&o=1&a=1568812361" width="1" height="1" border="0" alt="" style="border:none !important; margin:0px !important;" />