public void Download(string url, string savePath, string fileName)
{
Loom.RunAsync(() =>
{
asyncTask = new AsyncTask();
asyncTask.url = url;
asyncTask.savePath = savePath;
asyncTask.fileName = fileName;
//保存路径不存在则创建
if (!Directory.Exists(savePath))
{
Directory.CreateDirectory(savePath);
}
//创建请求
asyncTask.httpWebRequest = WebRequest.Create(url) as HttpWebRequest;
//创建文件流
asyncTask.fileStream = new FileStream(savePath + "/" + fileName, FileMode.OpenOrCreate, FileAccess.Write);
//获取已下载文件长度
asyncTask.fileLength = asyncTask.fileStream.Length;
//断点续传核心
//Seek 将该流的当前位置设置为给定值
asyncTask.fileStream.Seek(asyncTask.fileLength, SeekOrigin.Begin);
//向请求添加范围标头
asyncTask.httpWebRequest.AddRange((int)asyncTask.fileLength);
asyncTask.httpWebRequest.BeginGetResponse(new AsyncCallback(ResponseCallback), asyncTask);
});
}
void OnDestroy()
{
Instance = null;
}