动态导入资源

第一步：导入AssetBundle包
AssetBundle.LoadFromMemoryAsync//从内存中加载
AssetBundle.LoadFromFile //从硬盘中加载
WWW.LoadfromCacheOrDownload(将来会被UnityWebRequest替代)//从网络中加载
UnityWebRequest’s DownloadHandlerAssetBundle(5.3 or newer)

//从内存中以异步方式加载
IEnumerator Start(){
string path=”资源所在路径”;
AssetBundleCreateRequest request=AssetBundle.LoadFromMemoryAsync(File.ReadAllBytes(path));
yield return request;
AssetBundle bundle = request.assetBundle;

var prefab=bundle.LoadAsset(“MyObject”);
}
AssetBundleCreateRequest 是资源包异步创建请求的返回类，接收异步创建的结果，通过Bundle的二进制数据异步创建AssetBundle对象，完成后会在内存中创建较大的WebStream对象。如果构建时BuildAssetBundlesOptions.None（默认使用LZMA算法），下载完成后会使用线程对AssetBundle包进行解压缩。

//同步方式
AssetBundle ab=AssetBundle.LoadFromMemory(File.ReadAllBytes(path);

//从文件中加载
AssetBundleCreateRequest request=AssetBundle.LoadFromFile(path);

//从网络上加载
IEnumerator InstantiateObject(){
string uri=”“//统一资源路径
UnityWebRequest request=UnityWebRequest.GetAssetBundle(uri);
yield return request.Send();//Send才开始下载
AssetBundle ab=DownloadHandlerAssetBundle.GetContent(request);
或者AssetBundle ab=(request.downloadHandler as DownloadHandlerAssetBundle).assetBundle
}
第二步：加载资源
T objectFromBundle=bundleObject.LoadAsset< T >(assetName);
Object[] objectArray=loadedAssetBundle.LoadAllAssets();

AssetBundleRequest request=loadAssetBundleObject.LoadAssetAsync< T >(assetname);
yield return request;
资源会加载到内存中，不用时主动卸载