asp.net mvc 3.0 动态无损图片压缩，及路由定义

最新更新：120821

1.定义路由

2.编写控制器

3.编写图片压缩方法

4.测试运行

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1.定义路由 ，一般写在 Globals.cs 文件中

routes.MapRoute(
"ImgRoute", // 图片路由名称
"pics/{thumbnailType}/{width}/{height}/{*imgPath}", // 带有参数的 URL
new { controller = "Pictures", action = "ZoomImg", id = UrlParameter.Optional }, // 参数默认值
nameSpace);

2.编写控制器

public class ImagesController : Controller
{

/// <summary>
/// 缩放图片
/// </summary>
/// <param name="thumbnailType">图片缩放方式（取值参考：EB.Sys.Images.ImgThumbnail.ImgThumbnailType 枚举值）</param>
/// <param name="width">宽度</param>
/// <param name="height">高度</param>
/// <param name="imgPath">图片路径</param>
/// <returns></returns>
public string ZoomImg(string thumbnailType, string width, string height, string imgPath)
{
//return string.Format("{0} : {1} , {2} , {3} , {4}"
// ,DateTime.Now
// ,thumbnailType
// ,width
// ,height
// ,imgPath);

string sourceFile = Server.MapPath(string.Format("~/{0}", imgPath));

if (!System.IO.File.Exists(sourceFile))
return string.Format("图片路径无效:{0}", sourceFile);

ImgThumbnail.ImgThumbnailType type = (ImgThumbnail.ImgThumbnailType)thumbnailType.GetInt();

if (type == ImgThumbnail.ImgThumbnailType.Nothing)
return string.Format("压缩类型错误:{0}", thumbnailType);

EB.Sys.Images.ImgThumbnail.Thumbnail(
sourceFile
, Response.OutputStream
, width.GetInt()
, height.GetInt()
, 90
, type);
//测试输出流中是否存在内容
//byte[] arr = new byte[1000];
//Response.OutputStream.Write(arr,0,arr.Length);
return string.Empty;
}

}

3.编写图片压缩方法

这个方法在我另外一篇文章中有介绍，这里做了个加工

http://blog.csdn.net/xxj_jing/article/details/7715729

using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;
using System.IO;

namespace EB.Sys.Images
{
/// <summary>
/// 图片压缩
/// </summary>
public class ImgThumbnail
{
#region 枚举
/// <summary>
/// 指定缩放类型
/// </summary>
public enum ImgThumbnailType
{
/// <summary>
/// 无
/// </summary>
Nothing=0,
/// <summary>
/// 指定高宽缩放（可能变形）
/// </summary>
WH = 1,
/// <summary>
/// 指定宽，高按比例
/// </summary>
W = 2,
/// <summary>
/// 指定高，宽按比例
/// </summary>
H = 3,
/// <summary>
/// 指定高宽裁减（不变形）
/// </summary>
Cut = 4,
/// <summary>
/// 按照宽度成比例缩放后，按照指定的高度进行裁剪
/// </summary>
W_HCut = 5,
}
#endregion

#region 图片压缩
/// <summary>
/// 无损压缩图片
/// </summary>
/// <param name="sourceFile">原图片</param>
/// <param name="stream">压缩后保存到流中</param>
/// <param name="height">高度</param>
/// <param name="width"></param>
/// <param name="quality">压缩质量 1-100</param>
/// <param name="type">压缩缩放类型</param>
/// <returns></returns>
private static Bitmap Thumbnail(string sourceFile, int width, int height, int quality
, ImgThumbnailType type, out ImageFormat tFormat)
{
using (System.Drawing.Image iSource = System.Drawing.Image.FromFile(sourceFile))
{
tFormat = iSource.RawFormat;
//缩放后的宽度和高度
int toWidth = width;
int toHeight = height;
//
int x = 0;
int y = 0;
int oWidth = iSource.Width;
int oHeight = iSource.Height;

switch (type)
{
case ImgThumbnailType.WH://指定高宽缩放（可能变形）
{
break;
}
case ImgThumbnailType.W://指定宽，高按比例
{
toHeight = iSource.Height * width / iSource.Width;
break;
}
case ImgThumbnailType.H://指定高，宽按比例
{
toWidth = iSource.Width * height / iSource.Height;
break;
}
case ImgThumbnailType.Cut://指定高宽裁减（不变形）
{
if ((double)iSource.Width / (double)iSource.Height > (double)toWidth / (double)toHeight)
{
oHeight = iSource.Height;
oWidth = iSource.Height * toWidth / toHeight;
y = 0;
x = (iSource.Width - oWidth) / 2;
}
else
{
oWidth = iSource.Width;
oHeight = iSource.Width * height / toWidth;
x = 0;
y = (iSource.Height - oHeight) / 2;
}
break;
}
case ImgThumbnailType.W_HCut://按照宽度成比例缩放后，按照指定的高度进行裁剪
{
toHeight = iSource.Height * width / iSource.Width;
if (height < toHeight)
{
oHeight = oHeight * height / toHeight;
toHeight = toHeight * height / toHeight;
}
break;
}
default:
break;
}

Bitmap ob = new Bitmap(toWidth, toHeight);
//ImgWaterMark iwm = new ImgWaterMark();
//iwm.AddWaterMark(ob, towidth, toheight, "www.iqingcao.com");
Graphics g = Graphics.FromImage(ob);
g.Clear(System.Drawing.Color.WhiteSmoke);
g.CompositingQuality = CompositingQuality.HighQuality;
g.SmoothingMode = SmoothingMode.HighQuality;
g.InterpolationMode = InterpolationMode.HighQualityBicubic;
g.DrawImage(iSource
, new Rectangle(x, y, toWidth, toHeight)
, new Rectangle(0, 0, oWidth, oHeight)
, GraphicsUnit.Pixel);
g.Dispose();

return ob;

}
}
/// <summary>
/// 无损压缩图片
/// </summary>
/// <param name="sourceFile">原图片</param>
/// <param name="stream">压缩后保存到流中</param>
/// <param name="height">高度</param>
/// <param name="width"></param>
/// <param name="quality">压缩质量 1-100</param>
/// <param name="type">压缩缩放类型</param>
/// <returns></returns>
public static bool Thumbnail(string sourceFile, System.IO.Stream stream, int width,int height, int quality, ImgThumbnailType type)
{
ImageFormat tFormat = null;
Bitmap ob = Thumbnail(sourceFile, width, height, quality, type, out tFormat);
//水印
ImgWaterMark.AddWaterMark(ob, "www.iqingcao.com");
//以下代码为保存图片时，设置压缩质量
EncoderParameters ep = new EncoderParameters();
long[] qy = new long[1];
qy[0] = quality;//设置压缩的比例1-100
EncoderParameter eParam = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, qy);
ep.Param[0] = eParam;
try
{
ImageCodecInfo[] arrayICI = ImageCodecInfo.GetImageEncoders();
ImageCodecInfo jpegICIinfo = null;
for (int i = 0; i < arrayICI.Length; i++)
{
if (arrayICI[i].FormatDescription.Equals("JPEG"))
{
jpegICIinfo = arrayICI[i];
break;
}
}
if (jpegICIinfo != null)
{
ob.Save(stream, jpegICIinfo, ep);//jpegICIinfo是压缩后的新路径
}
else
{
ob.Save(stream, tFormat);
}
return true;
}
catch
{
return false;
}
finally
{
//iSource.Dispose();

ob.Dispose();

}
}

/// <summary>
/// 无损压缩图片
/// </summary>
/// <param name="sourceFile">原图片</param>
/// <param name="targetFile">压缩后保存位置</param>
/// <param name="height">高度</param>
/// <param name="width"></param>
/// <param name="quality">压缩质量 1-100</param>
/// <param name="type">压缩缩放类型</param>
/// <returns></returns>
public static bool Thumbnail(string sourceFile, string targetFile, int width, int height, int quality, ImgThumbnailType type)
{
ImageFormat tFormat = null;
Bitmap ob = Thumbnail(sourceFile, width, height, quality, type, out tFormat);
//以下代码为保存图片时，设置压缩质量
EncoderParameters ep = new EncoderParameters();
long[] qy = new long[1];
qy[0] = quality;//设置压缩的比例1-100
EncoderParameter eParam = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, qy);
ep.Param[0] = eParam;
try
{
ImageCodecInfo[] arrayICI = ImageCodecInfo.GetImageEncoders();
ImageCodecInfo jpegICIinfo = null;
for (int i = 0; i < arrayICI.Length; i++)
{
if (arrayICI[i].FormatDescription.Equals("JPEG"))
{
jpegICIinfo = arrayICI[i];
break;
}
}
if (jpegICIinfo != null)
{
ob.Save(targetFile, jpegICIinfo, ep);//jpegICIinfo是压缩后的新路径
}
else
{
ob.Save(targetFile, tFormat);
}
return true;
}
catch
{
return false;
}
finally
{
//iSource.Dispose();

ob.Dispose();

}
}
#endregion

}
}

4.测试运行

www.iqingcao.com/pics/5/195/395/images/ShangZhuang/610505/610505_00--w_498_h_498.jpg

在看一下路由定义：

"pics/{thumbnailType}/{width}/{height}/{*imgPath}"

{thumbnailType} 匹配 5

{width} 匹配 195

{height} 匹配 395

{*imgPath} 匹配 images/ShangZhuang/610505/610505_00--w_498_h_498.jpg

和控制器中的方法：

public string ZoomImg(string thumbnailType, string width, string height, string imgPath)

你明白的！参数列表命名相同！

给个测试地址：http://www.iqingcao.com/pics/5/195/395/images/ShangZhuang/610505/610505_00--w_498_h_498.jpg