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(0, 0, 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,0,0, 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