Unity uses AssetBundle to load resources

1. Set the AssetBundle name of the resource (if there is a material, you can also set it for the material, here the AssetBundle name of the material is share)

 2. Write a tool class to complete AssetBundle packaging

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEditor;
using System.IO;

public class AssetBundleAB
{
    [MenuItem("Assets/AssetBundle/BuildAB")]
    static void BuildAB()
    {
        Debug.Log("打包完成");
        string path = "Assets/AssetsBundles";
        if (!Directory.Exists(path))
        {
            Directory.CreateDirectory(path);
        }
        BuildPipeline.BuildAssetBundles(path, BuildAssetBundleOptions.UncompressedAssetBundle, BuildTarget.StandaloneWindows64);//三个参数分别表示打包路径，打包压缩格式，打包平台
        AssetDatabase.Refresh();//刷新
    }
}

after packing

 3. AssetBundle loading

Method 1: AssetBundle.LoadFromFile synchronous loading

using UnityEngine;

public class LoadResources : MonoBehaviour
{
    // Start is called before the first frame update
    void Start()
    {
        string path = "Assets/AssetsBundles/prefabs/Cube";
        AssetBundle ab = AssetBundle.LoadFromFile(path);//加载预制体AB包
        AssetBundle.LoadFromFile("Assets/AssetsBundles/share");//加载预制体的材质
        GameObject obj = ab.LoadAsset<GameObject>("Cube");//加载预制体
        Instantiate(obj);
    }
}

Method 2: AssetBundle.LoadFromFileAsync loads asynchronously

using System.Collections;
using UnityEngine;

public class LoadResources : MonoBehaviour
{
    // Start is called before the first frame update
    IEnumerator Start()
    {
        string path = "Assets/AssetsBundles/prefabs/Cube";
        AssetBundleCreateRequest request = AssetBundle.LoadFromFileAsync(path);
        yield return request;//等待响应
        AssetBundle ab = request.assetBundle;
        AssetBundleCreateRequest re = AssetBundle.LoadFromFileAsync("Assets/AssetsBundles/share");
        AssetBundle share = re.assetBundle;
        GameObject[] objs = ab.LoadAllAssets<GameObject>();
        foreach (var item in objs)
        {
            Instantiate(item);
        }
    }
}

Method 3: AssetBundle.LoadFromMemory synchronous loading

using UnityEngine;
using System.IO;

public class LoadResources : MonoBehaviour
{
    // Start is called before the first frame update
    void Start()
    {
        string path = "Assets/AssetsBundles/prefabs/Cube";
        AssetBundle cube = AssetBundle.LoadFromMemory(File.ReadAllBytes(path));
        AssetBundle mat = AssetBundle.LoadFromMemory(File.ReadAllBytes("Assets/AssetsBundles/share"));
        GameObject obj = cube.LoadAsset<GameObject>("Cube");
        Instantiate(obj);
    }
}

Method 4: AssetBundle.LoadFromMemoryAsync asynchronous loading

using UnityEngine;
using System.IO;
using System.Collections;

public class LoadResources : MonoBehaviour
{
    // Start is called before the first frame update
    IEnumerator Start()
    {
        string path = "Assets/AssetsBundles/prefabs/Cube";
        AssetBundleCreateRequest request = AssetBundle.LoadFromMemoryAsync(File.ReadAllBytes(path));
        yield return request;
        AssetBundle cube = request.assetBundle;
        AssetBundle.LoadFromMemoryAsync(File.ReadAllBytes("Assets/AssetsBundles/share"));
        GameObject obj = cube.LoadAsset<GameObject>("Cube");
        Instantiate(obj);
    }
}

Method 5: WWW asynchronous loading, loading in the form of a local directory (outdated, need to change the AssetsBundles folder name to StreamingAssets)

using UnityEngine;
using System.Collections;

public class LoadResources : MonoBehaviour
{
    // Start is called before the first frame update
    IEnumerator Start()
    {
        WWW www = new WWW("file:/"+Application.streamingAssetsPath+"/prefabs/cube");//本地目录需要加上"file://"
        WWW wwwMat = new WWW("file:/" + Application.streamingAssetsPath + "/share");
        yield return www;
        yield return wwwMat;
        AssetBundle cube = www.assetBundle;//获取ab包
        AssetBundle mat= wwwMat.assetBundle;//加载Asset
        GameObject obj = cube.LoadAsset<GameObject>("Cube");
        Instantiate(obj);
    }
}

Method 6: Asynchronous loading of UnityWebRequestAssetBundle (tested with NetBox2 local server)

NetBox2: Link: https://pan.baidu.com/s/1YsVFuoLGnukY_DRqiA7eyA?pwd=49ep 
Extraction code: 49ep

After downloading, just double-click to run it (Note: NetBox2 should be placed in the same directory as AssetsBundles)

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

public class LoadResources : MonoBehaviour
{
    // Start is called before the first frame update
    IEnumerator Start()
    {
        UnityWebRequest request = UnityWebRequestAssetBundle.GetAssetBundle("http://localhost/AssetsBundles/prefabs/cube");
        UnityWebRequest requestMat = UnityWebRequestAssetBundle.GetAssetBundle("http://localhost/AssetsBundles/share");
        yield return request.SendWebRequest();
        yield return requestMat.SendWebRequest();
        AssetBundle ab = DownloadHandlerAssetBundle.GetContent(request);//获取ab包
        AssetBundle mat = DownloadHandlerAssetBundle.GetContent(requestMat);
        GameObject obj = ab.LoadAsset<GameObject>("cube");//加载Asset
        Instantiate(obj);//实例化
    }
}