Unity UnityWebRequest 下载封装

对unity原生的UnityWebRequest 进行二次封装

public void UnityWebRequestLoad<T>(string path, Action<T> action, string localPath = "",
        AudioType audioType = AudioType.MPEG) where T : class
    {
    
        StartCoroutine(UnityWebRequestLoadAsync(path, action, localPath, audioType));
    }
    private IEnumerator UnityWebRequestLoadAsync<T>(string path, Action<T> action, string localPath = "",
        AudioType audioType = AudioType.MPEG) where T : class
    {
    
        UnityWebRequest req = new UnityWebRequest(path, UnityWebRequest.kHttpVerbGET);

        if (typeof(T) == typeof(byte[]))
            req.downloadHandler = new DownloadHandlerBuffer();
        else if (typeof(T) == typeof(File))
            req.downloadHandler = new DownloadHandlerFile(localPath);
        else if (typeof(T) == typeof(Texture2D))
            req.downloadHandler = new DownloadHandlerTexture();
        else if (typeof(T) == typeof(AssetBundle))
            req.downloadHandler = new DownloadHandlerAssetBundle(req.url, 0);
        else if (typeof(T) == typeof(AudioClip))
            req.downloadHandler = new DownloadHandlerAudioClip(req.url, audioType);
        else
        {
    
            Debug.LogWarning("未知类型:" + typeof(T));
            yield break;
        }

        yield return req.SendWebRequest();
        
        if (req.result == UnityWebRequest.Result.Success)
        {
    
            if (typeof(T) == typeof(byte[]))
                action?.Invoke(req.downloadHandler.data as T);
            else if (typeof(T) == typeof(File))
                action?.Invoke(null);
            else if (typeof(T) == typeof(Texture2D))
                action?.Invoke(DownloadHandlerTexture.GetContent(req) as T);
            else if (typeof(T) == typeof(AssetBundle))
                action?.Invoke(DownloadHandlerAssetBundle.GetContent(req) as T);
            else if (typeof(T) == typeof(AudioClip))
                action?.Invoke(DownloadHandlerAudioClip.GetContent(req) as T);
        }
        else
        {
    
            Debug.LogWarning("下载失败:" + req.result + req.error);
        }
    }