图像处理模式

/// <summary> 图像处理模式
/// </summary>
public enum ImageSizeMode
{
/// <summary> 原图,不做其他处理
/// </summary>
[CustomAttribute.Custom("原图", "N")]
None,

/// <summary> 居中 固定中心 剪裁或者留黑
/// </summary>
[CustomAttribute.Custom("居中", "C")]
Center,

/// <summary> 拉伸 变形 铺满
/// </summary>
[CustomAttribute.Custom("拉伸", "S")]
Stretch,

/// <summary> 适应 保持比率 留黑边
/// </summary>
[CustomAttribute.Custom("适应", "A")]
Adaptive,

/// <summary> 填充 保持比率 剪裁多余部分
/// </summary>
[CustomAttribute.Custom("填充", "F")]
Fill
}

/// <summary> 图像缓存
/// </summary>
public class ImageCache
{
/// <summary> 文件路径
/// </summary>
public string FullName { get; set; }

/// <summary> 数据
/// </summary>
public byte[] Data { get; set; }

/// <summary> 最后访问时间
/// </summary>
public DateTime LastTime { get; set; }
}

/// <summary> 图片资源库
/// </summary>
public class ImageResources
{
public static ImageResources Current
{
get { return _current; }
}

public ImageResources()
{
_path = Application.StartupPath + "\\";
CacheList = new Dictionary<string, ImageCache>();
}

ImageDraw draw = new ImageDraw();

private string _path;
private static readonly ImageResources _current = new ImageResources();

/// <summary> 图片存放路径 \ 结尾
/// </summary>
public string Path
{
get { return _path; }
set
{
_path = value.TrimEnd('/').TrimEnd('\\') + "\\";
if (!Directory.Exists(_path))
{
Directory.CreateDirectory(_path);
}
}
}

/// <summary> 缓存尺寸 MB 默认 1024
/// </summary>
public int CacheSize { get; set; }

/// <summary> 缓存 Key = Path Value.Key = 最后访问时间. Value.Value = 数据
/// </summary> 
public Dictionary<string, ImageCache> CacheList { get; set; }

/// <summary> 通过网络路径添加图像
/// </summary>
/// <param name="name"></param>
/// <param name="src"></param>
public void AddImageBySrc(string name, string src)
{
var wr = WebRequest.Create(src) as WebRequest;

var rs = wr.GetResponse().GetResponseStream();
var im = Image.FromStream(rs);

im.Save(Path + name);
}

/// <summary> 添加图像
/// </summary>
/// <param name="name"></param>
/// <param name="data"> </param>
public void AddImage(string name, byte[] data)
{
lock (Path)
{
File.WriteAllBytes(Path + name, data);
}
}

/// <summary> 添加图像
/// </summary>
/// <param name="name"></param>
/// <param name="data"></param>
public void AddImage(string name, HttpPostedFileBase data)
{
lock (Path)
{
data.SaveAs(Path + name);
}
}

/// <summary> 获取图像
/// </summary>
/// <param name="param"></param>
/// <returns></returns>
public byte[] GetImageByParam(string param)
{
var ii = param.FromJsone<ImageInfo>();

var bs = Current.GetImage(ii.N, new Size(ii.W, ii.H), ii.M.As(ImageSizeMode.None), ii.Q);

return bs;
}

/// <summary> 获取图像
/// </summary>
/// <param name="name"></param>
/// <param name="size"></param>
/// <param name="quality"> </param>
/// <param name="sizeModule"> </param>
public byte[] GetImage(string name, Size? size = null, ImageSizeMode sizeModule = ImageSizeMode.None, int quality = 90)
{
if (name.IsNullOrEmpty())
{
name = "Null.jpg";
}

string fn;
var isReturnSource = (size == null || sizeModule == ImageSizeMode.None);

if (isReturnSource)
{
fn = Path + name;
}
else
{
fn = Path + sizeModule.Value() + "_" + quality + "_" + size.Value.Width + "," + size.Value.Height + "/"
+ name + ".jpg";
}

var value = CacheList.TryGet(fn, () =>
{
try
{
lock (this)
{
byte[] data;
if (File.Exists(fn))
{
//缓存文件存在,直接返回
data = File.ReadAllBytes(fn);
}
else
{
// ReSharper disable PossibleInvalidOperationException
if (!File.Exists(Path + name))
{
//图片丢失 
name = "NoFind.jpg";
if (!File.Exists(Path + name))
{
//NoFind.jpg 也不存在.
return null;
}
}

if (isReturnSource)
{
//返回源图
return new ImageCache { Data = File.ReadAllBytes(Path + name) };
}

var img = Image.FromFile(Path + name);
var di = img;
switch (sizeModule)
//生成图片
{
case ImageSizeMode.Adaptive:
img = draw.GetAdaptiveImage(img, size.Value);
break;
case ImageSizeMode.Fill:
img = draw.GetFillImage(img, size.Value);
break;
case ImageSizeMode.Stretch:
img = draw.GetStretchImage(img, size.Value);
break;
default:
//没时间写.
throw new Exception("未知的图像处理方式!");
}

di.Dispose();

draw.SaveImageToJpeg(img, fn, quality);

data = GetImage(name, size, sizeModule, quality);
}
return new ImageCache { Data = data };
}
}
catch (Exception ex)
{
if (Query.Ip.IsIn("::1", "127.0.0.1"))
{
throw (ex.Message).ToException();
}
return null;
}
});

value.IsNotNull(j => j.LastTime = DateTime.Now);
return value.NotNull(j => j.Data);
}

/// <summary> 图像信息 用于 ToJsone
/// </summary>
private class ImageInfo
{
/// <summary> mode
/// </summary>
public string M { get; set; }

/// <summary> width
/// </summary>
public int W { get; set; }

/// <summary> height
/// </summary>
public int H { get; set; }

/// <summary> name 
/// </summary>
public string N { get; set; }

/// <summary> Quality
/// </summary>
public int Q { get; set; }
}

/// <summary> 获取文件参数
/// </summary>
/// <returns></returns>
public string GetImageParam(string name, ImageSizeMode mode = ImageSizeMode.None, int width = 0, int height = 0, int quality = 90)
{
var ii = new ImageInfo { N = name, M = mode.As(""), H = height, W = width, Q = quality };

return ii.ToJsone();
}

/// <summary> 获取ImageUrl
/// </summary>
/// <param name="name"></param>
/// <param name="mode"></param>
/// <param name="width"></param>
/// <param name="height"></param>
/// <returns></returns>
public string GetImageUrl(string name, ImageSizeMode mode = ImageSizeMode.None, int width = 0, int height = 0, int quality = 90)
{
return "/Image/" + GetImageParam(name, mode, width, height, quality);
}

/// <summary> 清理缩略图文件缓存
/// </summary>
public void ClearFileCache()
{
var ps = Directory.GetDirectories(Path);

foreach (var s in ps)
{
try
{
Directory.Delete(s, true);
}
catch
{ }
}
}
}
}