/// <summary>
/// 创建<see cref="Downloader"/>
/// </summary>
/// <param name="url">下载地址</param>
/// <param name="mirrors">镜像地址</param>
/// <param name="savePath">保存路径</param>
/// <param name="threadCount">下载线程数</param>
/// <param name="cacheLength">缓存大小，缓存可减少硬盘写入压力，不使用缓存可设置为<see cref="Downloader.EmptyCacheLength"/></param>
public Downloader(string url, IEnumerable <string> mirrors, string savePath, int threadCount, int cacheLength)
{
if (string.IsNullOrEmpty(url))
{
throw new ArgumentException("url can not be null or empty.");
}
if (string.IsNullOrEmpty(savePath))
{
throw new ArgumentException("savePath can not be null or empty.");
}
if (threadCount <= 0)
{
throw new ArgumentException("threadCount must bigger than 0.");
}
this._workID = EmptyWorkID;
this._segmentCalculator = new MinSizeSegmentCalculator(SegmentMinSize);
// 初始化_localFileCache
var mainSource = new FileSource(url);
List <FileSource> mirrorSources = null;
if (mirrors != null)
{
mirrorSources = new List <FileSource>();
foreach (var mirror in mirrors)
{
mirrorSources.Add(new FileSource(mirror));
}
}// if
this._config = new LocalFileConfig
{
MainSource = mainSource,
Mirrors = mirrorSources,
};
this._maxThreadCount = threadCount;
this._savePath = savePath;
this._configPath = DownloadHelper.GetConfigPathFromFilePath(savePath);
this._tmpPath = DownloadHelper.GetTmpPathFromFilePath(savePath);
this._cacheLength = cacheLength;
this._status = DownloaderStatuses.Idle;
}
/// <summary>
/// 创建<see cref="Downloader"/>
/// </summary>
/// <param name="configPath">本地文件</param>
/// <param name="threadCount">下载线程数</param>
/// <param name="cacheLength">缓存大小，缓存可减少硬盘写入压力，不使用缓存可设置为<see cref="Downloader.EmptyCacheLength"/></param>
public Downloader(string configPath, int threadCount, int cacheLength)
{
if (string.IsNullOrEmpty(configPath))
{
throw new ArgumentException("configPath can not be null or empty.");
}
var localFileConfig = LocalFileConfig.Load(configPath);
if (localFileConfig.MainSource == null)
{
throw new Exception("LocalFileConfig.MainSource can not be null.");
}
if (localFileConfig.RemoteInfo == null)
{
throw new Exception("LocalFileConfig.RemoteInfo can not be null.");
}
if (localFileConfig.RemoteInfo.Size < 0)
{
throw new Exception("LocalFileConfig.RemoteInfo.Size must bigger than 0.");
}
if (!localFileConfig.HasSegment)
{
throw new Exception("LocalFileConfig.Segments can not be empty.");
}
this._workID = EmptyWorkID;
this._segmentCalculator = new MinSizeSegmentCalculator(SegmentMinSize);
this._config = localFileConfig;
this._maxThreadCount = threadCount;
this._configPath = configPath;
this._savePath = DownloadHelper.GetFilePathFromConfigPath(configPath);
this._tmpPath = DownloadHelper.GetTmpPathFromFilePath(this._savePath);
this._cacheLength = cacheLength;
this._status = DownloaderStatuses.Idle;
}
/// <summary>
/// 通过配置文件创建<see cref="LocalFileConfig"/>
/// </summary>
/// <param name="path">配置文件路径</param>
/// <returns></returns>
public static LocalFileConfig Load(string path)
{
XDocument xml;
// 以UTF-8的格式加载配置文件
using (var reader = new StreamReader(path, Encoding.UTF8))
{
xml = XDocument.Load(reader);
}
LocalFileConfig fileInfo = new LocalFileConfig();
foreach (XElement field in xml.Root.Elements())
{
switch (field.Name.LocalName)
{
case "Source":
{
if (string.IsNullOrEmpty(field.Value))
{
break;
}
fileInfo._mainSource = FileSource.CreateFromXElement(field);
}
break;
case "Mirrors":
{
List <FileSource> mirrors = new List <FileSource>();
foreach (var mirror in field.Elements())
{
mirrors.Add(FileSource.CreateFromXElement(mirror));
}
fileInfo._mirrors = mirrors;
}
break;
case "RemoteInfo":
{
if (string.IsNullOrEmpty(field.Value))
{
break;
}
fileInfo._remoteInfo = RemoteFileInfo.CreateFromXElement(field);
}
break;
case "Segments":
{
List <LocalSegment> segments = new List <LocalSegment>();
foreach (var segment in field.Elements())
{
segments.Add(LocalSegment.CreateFromXElement(segment));
}
fileInfo._segments = segments;
}
break;
default:
break;
}
}// foreach
return(fileInfo);
}
