C# Bitmap构造函数代码示例

private void InitializeStreamBitmap()
{
    try
    {
        System.Net.WebRequest request = 
            System.Net.WebRequest.Create(
            "http://www.microsoft.com//h/en-us/r/ms_masthead_ltr.gif");
        System.Net.WebResponse response = request.GetResponse();
        System.IO.Stream responseStream = 
            response.GetResponseStream();
        Bitmap bitmap2 = new Bitmap(responseStream);
        PictureBox1.Image = bitmap2;
    }
    catch(System.Net.WebException)
    {
        MessageBox.Show("There was an error opening the image file."
           + "Check the URL");
    }
}

Bitmap image1;

private void Button1_Click(System.Object sender, System.EventArgs e)
{

    try
    {
        // Retrieve the image.
        image1 = new Bitmap(@"C:\Documents and Settings\All Users\" 
            + @"Documents\My Music\music.bmp", true);

        int x, y;

        // Loop through the images pixels to reset color.
        for(x=0; x<image1.Width; x++)
        {
            for(y=0; y<image1.Height; y++)
            {
                Color pixelColor = image1.GetPixel(x, y);
                Color newColor = Color.FromArgb(pixelColor.R, 0, 0);
                image1.SetPixel(x, y, newColor);
            }
        }

        // Set the PictureBox to display the image.
        PictureBox1.Image = image1;

        // Display the pixel format in Label1.
        Label1.Text = "Pixel format: "+image1.PixelFormat.ToString();
    }
    catch(ArgumentException)
    {
        MessageBox.Show("There was an error." +
            "Check the path to the image file.");
    }
}

private void ConstructFromResourceSaveAsGif(PaintEventArgs e)
{

    // Construct a bitmap from the button image resource.
    Bitmap bmp1 = new Bitmap(typeof(Button), "Button.bmp");

    // Save the image as a GIF.
    bmp1.Save("c:\\button.gif", System.Drawing.Imaging.ImageFormat.Gif);

    // Construct a new image from the GIF file.
    Bitmap bmp2 = new Bitmap("c:\\button.gif");

    // Draw the two images.
    e.Graphics.DrawImage(bmp1, new Point(10, 10));
    e.Graphics.DrawImage(bmp2, new Point(10, 40));

    // Dispose of the image files.
    bmp1.Dispose();
    bmp2.Dispose();
}

private void BitmapConstructorEx(PaintEventArgs e)
{

    // Create a bitmap.
    Bitmap bmp = new Bitmap("c:\\fakePhoto.jpg");
    
   // Retrieve the bitmap data from the bitmap.
    System.Drawing.Imaging.BitmapData bmpData = bmp.LockBits(new Rectangle(0, 0, bmp.Width, bmp.Height), 
        ImageLockMode.ReadOnly, bmp.PixelFormat);

    //Create a new bitmap.
    Bitmap newBitmap = new Bitmap(200, 200, bmpData.Stride, bmp.PixelFormat, bmpData.Scan0);

    bmp.UnlockBits(bmpData);

    // Draw the new bitmap.
    e.Graphics.DrawImage(newBitmap, 10, 10);
}