public void Start(Object o)
{
try
{
// 检查是否已经停止
if (task.Status == TaskStatus.Stop)
{
task.TaskStop(taskId, task);
task.Status = TaskStatus.Finish;
return;
}
task.TaskStart(taskId, task);
DownloadAndSave(task.Url, task.FilePath, task.FileName);
Console.WriteLine(taskId + "下载完成");
task.TaskFinish(taskId, task);
task.Status = TaskStatus.Finish;
}
catch (Exception e)
{
Console.WriteLine(e.Message);
// 进行最多三次重试
if (retry++ < 3)
{
Console.WriteLine(String.Format("[{0}]下载失败，第{1}次重试中", taskId, retry));
DownloadManager.Start(this);
}
else
{
Console.WriteLine(String.Format("[{0}]下载失败已超过三次，请检查网络是否可用", taskId, retry));
task.TaskFail(taskId, task);
task.Status = TaskStatus.Finish;
}
}
}
/// <summary>
/// 根据详情页url下载此页面，解析其中的图片地址并下载
/// </summary>
/// <param name="pageUrl"></param>
/// <param name="type"></param>
private void downloadPicture(string pageUrl, string type)
{
// 获取缓存路径
string[] arr = pageUrl.Split('/');
string pageId = arr[arr.Length - 2];
string cacheDir = homeDir + "cache\\";
CreateDir(cacheDir);
string cacheFile = cacheDir + pageId;
string pictureUrl = null;
// 从缓存中获取地址
if (File.Exists(cacheFile))
{
pictureUrl = File.ReadAllText(cacheFile);
if (pictureUrl == "")
{
pictureUrl = null;
}
}
if (pictureUrl == null)
{
//获取详情页面信息
string html = GetHtml(pageUrl);
// 检查页面是否下载成功
if (html == null || html == "")
{
throw new Exception("请检查网络");
}
//获取图片下载地址
pictureUrl = Analyze.GetPictureUrl(html);
if (pictureUrl == null)
{
throw new Exception("无法分析出图片地址：" + pageUrl);
}
// 缓存下来图片地址
CreateFile(cacheFile);
File.WriteAllText(cacheFile, pictureUrl);
}
// 获取文件名字
string pictureName = Analyze.GetFileName(pictureUrl);
// 文件完整路径
string fullFilePath = filePath + type + pictureName;
// 判断文件是否已经存在
if (File.Exists(fullFilePath))
{
AddItemToTextBox(String.Format("第{0}页第{1}张已存在，跳过", startPageNum, startPicNum));
startPicNum++;
skipDownloadNum++;
return;
}
// 使用多线程下载
Task task = new Task()
{
pageNum = startPageNum,
picNum = startPicNum,
Url = pictureUrl,
FilePath = filePath + type,
FileName = pictureName,
TaskStart = new Task.TaskStartDelegate(delegate(int id, Task t)
{
// 下载开始
}),
TaskStop = new Task.TaskStopDelegate(delegate(int id, Task t)
{
// AddItemToTextBox("下载被终止" + t.FileName);
}),
TaskFinish = new Task.TaskFinishDelegate(delegate(int id, Task t)
{
totalDownloadNum++;
// 计算下载所用时间
DateTime now = DateTime.Now;
TimeSpan time = now - startTime;
AddItemToTextBox(String.Format("第{0}页第{1}张下载完成，已经过{2}秒", t.pageNum, t.picNum, time.TotalSeconds));
}),
TaskFail = new Task.TaskFailDelegate(delegate(int id, Task t)
{
AddItemToTextBox(String.Format("第{0}页第{1}张下载失败", t.pageNum, t.picNum));
}),
};
DownloadManager.Add(task);
startPicNum++;
}
