从AssetBundle获取Hash128以获取Caching.IsVersionCached函数

1 回答

• 3

  但我不知道hash128是什么

  Hash128表示AssetBundle文件的哈希值，可以在下载时更轻松地比较AssetBundle文件版本 .

  我找不到如何使用hash128

  没有关于如何从文档中执行此操作的示例 . 以下是 three 获取Hash128的方法 . 使用哪一个取决于 AssetBundle 所在的条件以及是否要下载它以检查Hash128 . 在您的情况下， #1 很可能是您正在寻找的 .

  1 . Obtain Hash128 during AssetBundle build from the Editor then save to the Resources folder ：

  使用BuildPipeline.BuildAssetBundles函数构建AssetBundle时，此函数返回AssetBundleManifest . 您可以使用AssetBundleManifest.GetAssetBundleHash函数获取Hash128 . 将Hash128转换为带有Hash128.ToString()的字符串，然后将其保存到Resources文件夹，以便在运行时访问它 .

  将构建AssetBundle并将 Hash128 保存到Resources文件夹的 Editor 构建脚本示例：

  [MenuItem("Assets/Build AssetBundle")]
  static void ExportResource()
  {
      string folderName = "AssetBundles";
      string filePath = Path.Combine(Application.streamingAssetsPath, folderName);
  
      AssetBundleManifest assetMf = BuildPipeline.BuildAssetBundles(filePath, BuildAssetBundleOptions.None, BuildTarget.StandaloneWindows64);
  
      //Get Hash128 from the AssetBundleManifest
      Hash128 hash128 = assetMf.GetAssetBundleHash("AssetBundles");
  
      //Get the Hash128 as string
      string data = hash128.ToString();
      string path = "Assets/Resources/AssetInfo/AssetBundleInfo.txt";
  
      //Save the Hash128 to the Resources folder
      using (FileStream fileStream = new FileStream(path, FileMode.Create))
      {
          using (StreamWriter writer = new StreamWriter(fileStream))
          {
              writer.Write(data);
          }
      }
      UnityEditor.AssetDatabase.Refresh();
  }
  

  在运行时加载 Hash128 的简单函数：

  Hash128 getHash128(string path)
  {
      //Load from the Resources folder
      TextAsset txtAsset = (TextAsset)Resources.Load(path, typeof(TextAsset));
      string hash128 = txtAsset.text;
  
      return Hash128.Parse(hash128);
  }
  

  如何使用：

  //Load Hash128 from the Resources folder
  Hash128 tempHash128 = getHash128("AssetInfo/AssetBundleInfo");
  
  //Pass to the IsVersionCached function 
  Caching.IsVersionCached("yourUrl", tempHash128);
  

  你也可以根据需要使用json来表示和保存许多 Hash128 .

  ---

  2 . Download the AssetBundle from server then obtain Hash128 during run-time without the Resources folder . 不幸的是，您必须首先使用此方法下载AssetBundle，然后才能获得 Hash128 . 下载后，将数据加载为 AssetBundleManifest ，然后使用 AssetBundleManifest.GetAssetBundleHash 函数从中获取 Hash128 . 然后，您可以保存此 Hash128 供以后使用 .

  下面的示例应从AssetBundle URL下载并解压缩 Hash128 . 没有涉及编辑器代码 .

  IEnumerator downloadAssetBundle(string url)
  {
      UnityWebRequest www = UnityWebRequest.GetAssetBundle(url);
      yield return www.SendWebRequest();
  
      if (www.isNetworkError || www.isHttpError)
      {
          Debug.Log(www.error);
      }
      else
      {
          //Get the AssetBundle
          AssetBundle bundle = DownloadHandlerAssetBundle.GetContent(www);
  
          AssetBundleRequest asset = bundle.LoadAssetAsync<AssetBundleManifest>("assetManifestName");
          yield return asset;
  
          //Get the AssetBundleManifest
          AssetBundleManifest loadedAssetMf = asset.asset as AssetBundleManifest;
          //Get Hash128 from the AssetBundleManifest
          Hash128 tempHash128 = loadedAssetMf.GetAssetBundleHash("");
  
          //Pass to the IsVersionCached function 
          Caching.IsVersionCached("yourUrl", tempHash128);
      }
  }
  

  ---

  3 . Obtain Hash128 from an AssetBundle in the file system. 如果您已经是knew AssetBundle的路径，请从该路径加载AssetBundle，然后将数据加载为 AssetBundleManifest ，最后使用 AssetBundleManifest.GetAssetBundleHash 函数从中获取 Hash128 . 然后，您可以保存此 Hash128 供以后使用 .

  这显示了如何从StreamingAsset路径加载AssetBundle并获取其 Hash128 ：

  IEnumerator loadAssetManifest(string assetBundleName, string assetManifestName)
  {
      string filePath = System.IO.Path.Combine(Application.streamingAssetsPath, "AssetBundles");
      filePath = System.IO.Path.Combine(filePath, assetBundleName);
  
      var assetBundleCreateRequest = AssetBundle.LoadFromFileAsync(filePath);
      yield return assetBundleCreateRequest;
  
      AssetBundle asseBundle = assetBundleCreateRequest.assetBundle;
  
      AssetBundleRequest asset = asseBundle.LoadAssetAsync<AssetBundleManifest>(assetManifestName);
      yield return asset;
  
      //Get the AssetBundleManifest
      AssetBundleManifest loadedAssetMf = asset.asset as AssetBundleManifest;
      //Get Hash128 from the AssetBundleManifest
      Hash128 tempHash128 = loadedAssetMf.GetAssetBundleHash("");
  
      //Pass to the IsVersionCached function 
      Caching.IsVersionCached("yourUrl", tempHash128);
  }
  

  回复于 2024-04-29T10:16:45+08:00