Unity3D资源异步加载——图片音视频资源加载

Posted 2021-03-01

这几天一直做优化的事情，对于资源这一块优化，资源异步加载作为首选，因2018之后版本中弃用了WWW请求，所以今天我们以UnityWebRequest 请求方式介绍，基本上是一个整理。

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Networking;

public class ResourceLoad : MonoBehaviour
{
    /// <summary>
    /// 单例
    /// </summary>
    private static ResourceLoad _instance = null;
    public static ResourceLoad Instance {
        get {

            if(null == _instance)
            {
                GameObject singleton = (GameObject)UnityEngine.Object.FindObjectOfType(typeof(GameObject));
                if(null == singleton)
                {
                    singleton = new GameObject("Singleton");
                    DontDestroyOnLoad(singleton);
                }

                _instance = singleton.GetComponent<ResourceLoad>();
                if (null == _instance)
                {
                    _instance = singleton.AddComponent<ResourceLoad>();
                }
            }

            return _instance;
        }
    }

    /*UnityWebRequests处理与Web服务器的HTTP通信流。
     * 其他对象-特别是DownloadHandler和UploadHandler-分别控制数据的下载和上传。
     * 为了方便起见，提供了一组静态函数。这些将返回为许多常见用例正确配置的UnityWebRequest对象。请参阅： Get，Post，Put，GetTexture。
     * 可以对下面属性了解
     * responseCode  服务器返回的数字HTTP响应代码，例如200、404或500。（只读）
     * timeout   设置UnityWebRequest以尝试在超时秒数过去后中止。
     * downloadProgress     返回介于0.0和1.0之间的浮点值，指示从服务器下载正文数据的进度。（只读）
     * 返回介于0.0和1.0之间的浮点值，指示将主体数据上传到服务器的进度。
     * useHttpContinue  确定此UnityWebRequest是否在其传出请求标头中包含Expect：100-Continue。（默认值：true）。
     * SendWebRequest   开始与远程服务器通信。
     * SetRequestHeader 将HTTP请求标头设置为自定义值。
     * Head Creates a UnityWebRequest configured to send a HTTP HEAD request.
     */

    #region--//对请求分装
     /// <summary>
     /// get请求
     /// </summary>
     /// <param name="url"></param>
     /// <param name="actionResult"></param>
     public void WebquestGet(string url, System.Action<bool, string> actionResult)
     {
        StartCoroutine(_Get(url, actionResult));
    }
    /// <summary>
    /// Sprite请求
    /// </summary>
    /// <param name="url"></param>
    /// <param name="actionResult"></param>
     public void WebquestGet(string url, System.Action<bool, string, Sprite> actionResult)
     {
        StartCoroutine(_GetTexture(url, actionResult));
     }

    // .
    // .
    // .
    // . 省略

    #endregion

    #region --- 网络请求
    /// <summary>
    /// GET请求
    /// </summary>
    /// <param name="url">请求地址</param>
    /// <param name="action">请求发起后处理回调结果的委托</param>
    /// <returns></returns>
    IEnumerator _Get(string url, System.Action<bool, string> actionResult)
    {
        using (UnityWebRequest quest = UnityWebRequest.Get(url))
        {
            yield return quest.SendWebRequest();
            string msg = "";
            if (!(quest.isNetworkError || quest.isHttpError))
            {
                msg = quest.downloadHandler.text;
            }
            else
            {
                msg = quest.error;
            }
            if (actionResult != null)
            {
                actionResult.Invoke(quest.isHttpError, msg);
            }
        }
    }

    /// <summary>
    /// 请求文件byte
    /// </summary>
    /// <param name="url"></param>
    /// <param name="action">请求发起后处理回调结果的委托,处理请求结果的byte数组</param>
    /// <returns></returns>
    IEnumerator _GetBytes(string url, System.Action<bool, string, byte[]> actionResult)
    {

        using (UnityWebRequest quest = new UnityWebRequest(url))
        {
            DownloadHandlerFile downloadFile = new DownloadHandlerFile(url);
            quest.downloadHandler = downloadFile;
            yield return quest.SendWebRequest();
            byte[] bytes = null;
            string text = null;
            if (!(quest.isNetworkError || quest.isHttpError))
            {
                bytes = downloadFile.data;
            }
            else
            {
                text = quest.error;
            }
            if (actionResult != null)
            {
                actionResult.Invoke((quest.isNetworkError || quest.isHttpError), text, bytes);
            }
        }
    }

    /// <summary>
    /// 请求Sprite和图片
    /// </summary>
    /// <param name="url">图片地址‘</param>
    /// <param name="action">请求发起后处理回调结果的委托,处理请求结果的图片</param>
    /// <returns></returns>
    IEnumerator _GetTexture(string url, System.Action<bool, string, Sprite> actionResult)
    {
        using (UnityWebRequest quest = UnityWebRequestTexture.GetTexture(url)) // 或者直接用 new UnityWebRequest(url)
        {
            //DownloadHandlerTexture downloadTexture = new DownloadHandlerTexture(true);
            //quest.downloadHandler = downloadTexture;
            yield return quest.SendWebRequest();
            string text = null;
            Sprite sprite = null;

            if (!(quest.isNetworkError || quest.isHttpError))
            {
                Texture2D texture = DownloadHandlerTexture.GetContent(quest); //downloadTexture.texture;
                sprite = Sprite.Create(texture, new Rect(0, 0, texture.width, texture.height), new Vector2(0.5f, 0.5f));

            }
            else
            {
                text = quest.error;
            }
            if (actionResult != null)
            {
                actionResult.Invoke((quest.isNetworkError || quest.isHttpError), text, sprite);
            }
        }
    }

    /// <summary>
    /// 请求服务器地址上的音效
    /// </summary>
    /// <param name="url">没有音频地址</param>
    /// <param name="actionResult">请求发起后处理回调结果的委托,处理请求结果的MovieTexture</param>
    /// <param name="audioType">音效类型</param>
    /// <returns></returns>
    IEnumerator _GetAudioClip(string url, System.Action<bool, string, AudioClip> actionResult, AudioType audioType = AudioType.WAV)
    {
        using (UnityWebRequest quest = UnityWebRequest.Get(url))
        {
            DownloadHandlerAudioClip downloadAudioClip = new DownloadHandlerAudioClip(url, audioType);
            quest.downloadHandler = downloadAudioClip;
            yield return quest.SendWebRequest();
            AudioClip audioClip = null;
            string text = null;
            if (!(quest.isNetworkError || quest.isHttpError))
            {
                audioClip = downloadAudioClip.audioClip;
            }
            else
            {
                text = quest.error;
            }
            if (actionResult != null)
            {
                actionResult.Invoke((quest.isNetworkError || quest.isHttpError), text, audioClip);
            }
        }
    }

    /// <summary>
    /// 向服务器提交post请求
    /// </summary>
    /// <param name="url">服务器请求目标地址</param>
    /// <param name="formData">form表单参数</param>
    /// <returns></returns>
    IEnumerator _Post(string url, string formData, System.Action<bool, string> actionResult)
    {

        using (UnityWebRequest quest = UnityWebRequest.Post(url, formData))
        {
            //发送数据
            setWebRequest(quest, formData);
            yield return quest.SendWebRequest();
            string text = "";
            if (!(quest.isNetworkError || quest.isHttpError))
            {
                text = quest.downloadHandler.text;
            }
            else
            {
                text = quest.error;
            }
            if (actionResult != null)
            {
                actionResult.Invoke(quest.isHttpError, text);
            }
        }
    }

    /// <summary>
    /// 设置表头和发送信息
    /// </summary>
    /// <param name="quest"></param>
    /// <param name="info"></param>
    void setWebRequest(UnityWebRequest quest, string info)
     {
        //设置发送表头信息
        quest.SetRequestHeader("Content-Type", "application/json");

        //设置发送的信息
        Object objectInfo = null;//(设置info 类结构对象信息)
        string jsonId = JsonUtility.ToJson(objectInfo);
        byte[] wForm = System.Text.Encoding.UTF8.GetBytes(jsonId);
        quest.uploadHandler = new UploadHandlerRaw(wForm);
        quest.downloadHandler = new DownloadHandlerBuffer();

        //或者
        //List<IMultipartFormSection> formData = new List<IMultipartFormSection>();
        //formData.Add(new MultipartFormDataSection("field1=foo&field2=bar"));
        //formData.Add(new MultipartFormFileSection("my file data", "myfile.txt"));
    }

    #endregion

}