ASP.NET:调整上传到服务器的图像的大小(高度和宽度)
答
试试下面的方法:System.Drawing命名空间内
public string ResizeImageAndSave(int Width, int Height, string imageUrl, string destPath)
{
System.Drawing.Image fullSizeImg = System.Drawing.Image.FromFile(imageUrl);
double widthRatio = (double)fullSizeImg.Width/(double)Width;
double heightRatio = (double)fullSizeImg.Height/(double)Height;
double ratio = Math.Max(widthRatio, heightRatio);
int newWidth = (int)(fullSizeImg.Width/ratio);
int newHeight = (int)(fullSizeImg.Height/ratio);
//System.Drawing.Image.GetThumbnailImageAbort dummyCallBack = new System.Drawing.Image.GetThumbnailImageAbort(ThumbnailCallback);
System.Drawing.Image thumbNailImg = fullSizeImg.GetThumbnailImage(newWidth, newHeight, new System.Drawing.Image.GetThumbnailImageAbort(ThumbnailCallback), IntPtr.Zero);
//DateTime MyDate = DateTime.Now;
//String MyString = MyDate.ToString("ddMMyyhhmmss") + imageUrl.Substring(imageUrl.LastIndexOf("."));
thumbNailImg.Save(destPath, ImageFormat.Jpeg);
thumbNailImg.Dispose();
return "";
}
public bool ThumbnailCallback() { return false; }
答
你试过吗?
public Image resize(Image img, int width, int height)
{
Bitmap b = new Bitmap(width, height) ;
Graphics g = Graphics.FromImage((Image) b) ;
g.DrawImage(img, 0, 0, width, height) ;
g.Dispose() ;
return (Image) b ;
}
+1
注重要(http://msdn.microsoft.com/en-us/library/system.drawing.aspx)>类不支持在Windows或ASP.NET服务中使用。 – 2009-10-16 11:26:04
答
片断我总是用:
var target = new Bitmap(size.Width, size.Height, PixelFormat.Format24bppRgb);
target.SetResolution(source.HorizontalResolution,
source.VerticalResolution);
using (var graphics = Graphics.FromImage(target))
{
graphics.Clear(Color.White);
graphics.InterpolationMode = InterpolationMode.HighQualityBicubic;
graphics.DrawImage(source,
new Rectangle(destX, destY, destWidth, destHeight),
new Rectangle(sourceX, sourceY, source.Width, source.Height),
GraphicsUnit.Pixel);
}
回报目标;
+1
注意重要(http://msdn.microsoft.com/zh-cn/library/system.drawing.aspx)> System.Drawing命名空间中的类不支持在Windows或ASP.NET服务中使用。 – 2009-10-16 11:26:51
和文件大小?我也想减小文件大小。 – VansFannel 2009-10-17 06:09:33