An eXtensible Car Description format with ATL COM

// This source code is provided as C# sample to use the XCD Library.
// Copyright © 2011 MSB LLC. All rights reserved.

using System;
using System.Drawing;
using System.Windows.Forms;
using XCD;
using Microsoft.VisualBasic.Compatibility.VB6; // IPicture support

namespace XCD_Client_CS
{
    public partial class frmXCDClient : Form
    {
        public frmXCDClient()
        {
            InitializeComponent();
        }

        private void XCD_Client_CS_Load(object sender, EventArgs e)
        {
            objCollection = new XCD.Collection();
            objCar = new XCD.Car();

            cboTagName.Items.Add("Year");
            cboTagName.Items.Add("Make");
            cboTagName.Items.Add("Model");
            cboTagName.Items.Add("Submodel");
            cboTagName.Items.Add("Type");
            cboTagName.Items.Add("Price");
            cboTagName.Items.Add("Country");
            cboTagName.Items.Add("Length");
            cboTagName.Items.Add("Width");
            cboTagName.Items.Add("Height");
            cboTagName.Items.Add("Weight");
            cboTagName.Items.Add("Power");
            cboTagName.Items.Add("Fuel");
            cboTagName.Items.Add("Clearance");
            cboTagName.Items.Add("Tank Volume");

            cboTagName.SelectedIndex = 0;

            btnGetPictureTitle.Enabled = false;
            btnShowPicture.Enabled = false;
            btnGetValue.Enabled = false;
        }

        private void btnSelectCARFile_Click(object sender, EventArgs e)
        {
            int nItemCount;
            OpenFileDialog ofd = new OpenFileDialog();

            ofd.Filter = "CAR Files (*.car)|*.car";
            ofd.RestoreDirectory = true;
            ofd.Title = "Select Car Collection File";

            if (ofd.ShowDialog() == DialogResult.OK)
            {
                objCollection.FFN = ofd.FileName;

                if (objCollection.IsCarFile())
                {
                    nItemCount = objCollection.GetCount();

                    txtFFN.Text = ofd.FileName;
                    txtCollectionTitle.Text = objCollection.GetTitle();

                    txtCollectionItemCount.Text = nItemCount.ToString();
                    txtCollectionVersion.Text = objCollection.GetVersion();
                    txtCollectionXCDVersion.Text = 
                                                  objCollection.GetXCDVersion();

                    nudItem.Minimum = 0;
                    nudItem.Maximum = nItemCount - 1;

                    btnGetPictureTitle.Enabled = true;
                    btnShowPicture.Enabled = true;
                    btnGetValue.Enabled = true;
                }
                else
                    MessageBox.Show("The file is not a CAR file!", 
                                                               "XCD_CS_Client");
            }                   
        }

        private void btnGetPictureTitle_Click(object sender, EventArgs e)
        {
            txtPictureTitle.Text = objCar.GetPictureTitle(
                                                         (ushort)nudItem.Value);
        }

        private void btnShowPicture_Click(object sender, EventArgs e)
        {
            stdole.IPicture picture = null;
			int intHeight;
			int intWidth;
			double dblScaleX;
			int intPictureBoxHeight; 

            picture = objCar.GetPicture((ushort)nudItem.Value);
			// Microsoft.VisualBasic.Compatibility.VB6 does not have 
			// TwipsPerPixelX (Y) properties like in VB so function 
			// GetTwipsPerPixel is added.
            intHeight = picture.Height / (int)GetTwipsPerPixel("X");
			intWidth = picture.Width / (int)GetTwipsPerPixel("Y");

			dblScaleX = (double)picCarImage.Width / (double)intWidth;
			intPictureBoxHeight = (int)(dblScaleX * intHeight);
			// Center vertically. 
			picCarImage.Top = picCarImage.Location.Y + 
				                 (picCarImage.Height - intPictureBoxHeight) / 2; 
            picCarImage.Height = intPictureBoxHeight;
			picCarImage.SizeMode = PictureBoxSizeMode.StretchImage;
            picCarImage.Image = Support.IPictureToImage(picture); 
        }

        private void btnGetValue_Click(object sender, EventArgs e)
        {
            txtTagValue.Text = objCar.GetValue((ushort)nudItem.Value, 
                                                               cboTagName.Text); 
        }

        private void lnkSite_Clicked(object sender, 
                                                LinkLabelLinkClickedEventArgs e)
        {
            System.Diagnostics.Process.Start(
                                         "www.myscreensaverbuilder.com/CE.htm");
        }

        private double GetTwipsPerPixel(string strDirection)
        {
            const int LOGPIXELSX = 88;
            const int LOGPIXELSY = 90;
            const int intTwipsPerInch = 1440;
            int intIndex;
            int intPixelsPerInch;
            double dblTwipsPerPixel;

            Graphics gfx = this.CreateGraphics();
            IntPtr hDC = gfx.GetHdc();

            if (strDirection == "X")
                intIndex = LOGPIXELSX;
            else if (strDirection == "Y")
                intIndex = LOGPIXELSY;
            else
                intIndex = LOGPIXELSX;

            // Get number of pixels per logical inch along the screen width or 
            // height.
            intPixelsPerInch = GetDeviceCaps(hDC, intIndex);

            dblTwipsPerPixel = (double)intTwipsPerInch /
                                                       (double)intPixelsPerInch;
            gfx.ReleaseHdc(hDC);

            return dblTwipsPerPixel;
        }
    }
}