/// <summary>
/// 下载文件
/// </summary>
/// <param name="url"></param>
/// <param name="type"></param>
/// <param name="callback"></param>
/// <param name="cachePath">缓存到本地的相对目录，如果为null则不缓存</param>
/// <param name="retry"></param>
public static void Download(string url, FileDownloadType type, FileDownloadCallback callback, string cachePath = null, int retry = 0)
{
if (downloader == null)
{
downloader = new FileDownloader();
Updater.Instance.OnPreUpdate.Add(downloader.OnUpdate);
Updater.Instance.OnPostDestroy.Add(downloader.OnDestroy);
}
FileDownloadContext ctx = new FileDownloadContext();
ctx.url = url;
ctx.type = type;
ctx.callback = callback;
ctx.retry = retry;
ctx.cachePath = cachePath;
if (downloader.CheckCache(ctx))
{
if (ctx.callback != null)
{
ctx.callback(ctx);
}
return;
}
downloader.sendQueue.Enqueue(ctx);
}
bool CheckCache(FileDownloadContext ctx)
{
switch (ctx.type)
{
case FileDownloadType.Texture: {
WeakReference wr;
if (textures.TryGetValue(ctx.url, out wr) && wr.IsAlive)
{
ctx.texture = wr.Target as Texture2D;
return(true);
}
break;
}
}
return(false);
}
IEnumerator _Send()
{
busy = true;
FileDownloadContext ctx = sendQueue.Dequeue();
string url = ctx.url;
Debug.Log("下载: " + url);
if (CheckCache(ctx))
{
if (ctx.callback != null)
{
ctx.callback(ctx);
}
busy = false;
yield break;
}
string cacheFn = null;
if (ctx.cachePath != null)
{
cacheFn = GetCacheFilename(url, cacheFn);
using (WWW www = new WWW("file://" + WWW.EscapeURL(cacheFn, Encoding.Default))) {
yield return(www);
if (www.error != null)
{
}
else
{
switch (ctx.type)
{
case FileDownloadType.Texture: {
ctx.texture = www.textureNonReadable;
textures[ctx.url] = new WeakReference(ctx.texture);
break;
}
case FileDownloadType.Binary: {
ctx.bytes = www.bytes;
break;
}
}
if (ctx.callback != null)
{
ctx.callback(ctx);
}
busy = false;
yield break;
}
}
}
while (ctx.retry >= 0)
{
using (WWW www = new WWW(url)) {
yield return(www);
if (www.error != null)
{
ctx.error = www.error;
Debug.LogError("下载: " + url + " Err:" + ctx.error);
}
else
{
bool save = false;
switch (ctx.type)
{
case FileDownloadType.Texture: {
ctx.texture = www.texture;
textures[ctx.url] = new WeakReference(ctx.texture);
save = ctx.texture != null;
break;
}
case FileDownloadType.Binary: {
ctx.bytes = www.bytes;
save = ctx.bytes != null;
break;
}
}
if (save && cacheFn != null)
{
string dir = Path.GetDirectoryName(cacheFn);
if (!Directory.Exists(dir))
{
Directory.CreateDirectory(dir);
}
File.WriteAllBytes(cacheFn, www.bytes);
}
}
}
ctx.retry--;
}
if (ctx.callback != null)
{
ctx.callback(ctx);
}
busy = false;
}
