问题描述
我正在开发中,我让我的用户上传无论是JPEG,GIF,BMP或PNG图像的ASP.NET 3.5 Web应用程序。如果上传的图像尺寸大于103×32的我要调整上传的图片,以103点¯x32.我看过一些博客文章和文章,也曾尝试一些code样品,但似乎没有任何工作对。有没有人在做这个成功吗?
I am developing an ASP.NET 3.5 web application in which I am allowing my users to upload either jpeg,gif,bmp or png images. If the uploaded image dimensions are greater then 103 x 32 the I want to resize the uploaded image to 103 x 32. I have read some blog posts and articles, and have also tried some of the code samples but nothing seems to work right. Has anyone succeed in doing this?
推荐答案
我有同样的问题而回,并处理了这种方式:
I had the same problem a while back and dealt with it this way:
private Image RezizeImage(Image img, int maxWidth, int maxHeight)
{
if(img.Height < maxHeight && img.Width < maxWidth) return img;
using (img)
{
Double xRatio = (double)img.Width / maxWidth;
Double yRatio = (double)img.Height / maxHeight;
Double ratio = Math.Max(xRatio, yRatio);
int nnx = (int)Math.Floor(img.Width / ratio);
int nny = (int)Math.Floor(img.Height / ratio);
Bitmap cpy = new Bitmap(nnx, nny, PixelFormat.Format32bppArgb);
using (Graphics gr = Graphics.FromImage(cpy))
{
gr.Clear(Color.Transparent);
// This is said to give best quality when resizing images
gr.InterpolationMode = InterpolationMode.HighQualityBicubic;
gr.DrawImage(img,
new Rectangle(0, 0, nnx, nny),
new Rectangle(0, 0, img.Width, img.Height),
GraphicsUnit.Pixel);
}
return cpy;
}
}
private MemoryStream BytearrayToStream(byte[] arr)
{
return new MemoryStream(arr, 0, arr.Length);
}
private void HandleImageUpload(byte[] binaryImage)
{
Image img = RezizeImage(Image.FromStream(BytearrayToStream(binaryImage)), 103, 32);
img.Save("IMAGELOCATION.png", System.Drawing.Imaging.ImageFormat.Gif);
}
我刚刚看了说,这是获得最高质量的方式。
I just read that this was the the way to get highest quality.
这篇关于调整大小在asp.net中的图像,而不会丢失图像质量的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!