使用WebClient在Unity3d中下载大文件

Question

我正在寻找有关使用WebClient在Unity3d中下载大（100mg +）文件的任何想法。 WWW以异步方式运行并且完美无缺，除非它返回内存错误并导致应用程序崩溃，因此我已按照此处所述移至解决方案：

如何从网址下载文件并使用C sharp中的unity3d保存在位置？

这就像一个梦想， 除了它关闭我的应用程序中的所有脚本，直到下载完成。 我似乎无法在下载进行的同时运行加载栏。 我已经尝试通过添加协程来处理下载，但到目前为止，没有运气。

任何帮助，将不胜感激。 我的代码目前（经过多次迭代）看起来像：

C＃

 void Update()
    {
    //Sets up the timer so I can use it to watch the debugging
        timer += Time.deltaTime;
        Debug.Log (timer);

//Checks to see if the file was already downloaded and saved.  If not, it begins downloading.
    if (FileExists == 0 && timer >= 5) {
        StartCoroutine ("DOWNLOAD");

    } 
//If the file already exists, it jumps straight to the next scene.
    else if (FileExists == 1) {
        Application.LoadLevelAsync ("Different_Level");
    }

    //These are the buttons.  One should stop the download if the player decides they don't want to wait.
    if (Input.GetMouseButtonUp (0)) {

        RaycastHit rc_hit;
        Ray hud_ray = Camera.main.ScreenPointToRay (Input.mousePosition);

    if (Physics.Raycast (hud_ray, out rc_hit, Mathf.Infinity, 1 << LayerMask.NameToLayer ("HUD"))) {

    if (rc_hit.transform.gameObject == b_BackButton) {

        StopCoroutine ("EN_Loop");
        Application.LoadLevelAsync ("Other_Level"); 
                            }
                    }
            }

}

//This is what should happen when the video is done downloading
void AllDone ()

{
    Debug.Log ("Download Complete");
    Application.LoadLevelAsync ("Next_Level");
}

////This is the coroutine I created int he hopes that I could get the download to run in the background.
IEnumerator DOWNLOAD()
{
    Debug.Log("downloading_EN");
    WebClient client = new WebClient();
    client.DownloadFile ("http://ServerInfo.net/moviefile.mp4", Application.persistentDataPath + "/" + "moviefile.mp4");
    yield return null;

    AllDone ();

}

Answer 1

尝试使用WebClient.DownloadFileAsync来锁定主线程（这样您的其他脚本仍将运行）并使用WebClient.DownloadFileCompleted事件来了解它何时完成。

无需使用Coroutine来使用WebClient，并确保只调用此方法一次：

void DownloadFile()
{
    WebClient client = new WebClient();
    client.DownloadFileCompleted += new System.ComponentModel.AsyncCompletedEventHandler( DownloadFileCompleted );
    client.DownloadFileAsync ((new Uri ("http://ServerInfo.net/moviefile.mp4", Application.persistentDataPath + "/" + "moviefile.mp4"));
}

void DownloadFileCompleted(object sender, System.ComponentModel.AsyncCompletedEventArgs e)
{
    if (e.Error == null)
    {
        AllDone ();
    }
}

有关DownloadFileAsync的更多信息：

https://msdn.microsoft.com/en-us/library/system.net.webclient.downloadfileasync%28v=vs.110%29.aspx

和DownloadFileCompleted事件：

https://msdn.microsoft.com/en-us/library/system.net.webclient.downloadfilecompleted%28v=vs.110%29.aspx