net图片转格式

http://blog.csdn.net/nrlovestudy/article/details/48137339

图片转格式

Bitmap bmp=new Bitmap("filename");
bmp.Save(".bmp",ImageFormat.bbp24);

Image imgOriginal = Image.FromFile(strOriginalImagePath);

Image imgOriginal = Image.FromStream(fileImg.InputStream);

using (Bitmap source = new Bitmap("source.jpg"))
            {
                using (Bitmap bmp = new Bitmap(source.Width, source.Height, System.Drawing.Imaging.PixelFormat.Format24bppRgb))
                {
                    Graphics.FromImage(bmp).DrawImage(source, new Rectangle(, , bmp.Width, bmp.Height));
                    bmp.Save("result.bmp", System.Drawing.Imaging.ImageFormat.Bmp);
                }
            }

public class imgConvert
{
    private void BMPToJPG(string bmpFileName,string jpgFileName)
    {  

       System.Drawing.Image img;
       img=ReturnPhoto(bmpFileName);  

       img.Save(jpgFileName,ImageFormat.Jpeg);
    }  

    private Image ReturnPhoto(string bmpFileName)
    {
       System.IO.FileStream stream ;
       stream=File.OpenRead(bmpFileName);
       Bitmap bmp = new Bitmap(stream);
       System.Drawing.Image image = bmp;//得到原图
       //创建指定大小的图
       System.Drawing.Image newImage = image.GetThumbnailImage(bmp.Width, bmp.Height,null, new IntPtr());
       Graphics g=Graphics.FromImage(newImage);
       g.DrawImage(newImage,,, newImage.Width, newImage.Height); //将原图画到指定的图上
       g.Dispose();
       stream.Close();
       return newImage;
    }
}  

文本创建图片

http://www.cnblogs.com/insus/archive/2013/03/08/2950300.html