UnityWebRequestでasync awaitする メモ

UnityWebRequestでIEnumeratorを使いたくないので、いろいろ検索

■参照元
https://gist.github.com/krzys-h/9062552e33dd7bd7fe4a6c12db109a1a

名前空間ではまったのでメモ
UnityEngeineないと下記でコンパイルエラー
(asyncOp.completed += OnRequestCompleted;)

■Awaiterクラス作成とGetAwaiterによる拡張

using System;
using System.Runtime.CompilerServices;
using UnityEngine;
using UnityEngine.Networking;

public class UnityWebRequestAwaiter : INotifyCompletion
{
    private UnityWebRequestAsyncOperation asyncOp;
    private Action continuation;

    public UnityWebRequestAwaiter(UnityWebRequestAsyncOperation asyncOp)
    {
        this.asyncOp = asyncOp;
        asyncOp.completed += OnRequestCompleted;
    }

    public bool IsCompleted { get { return asyncOp.isDone; } }

    public void GetResult() { }

    public void OnCompleted(Action continuation)
    {
        this.continuation = continuation;
    }

    private void OnRequestCompleted(AsyncOperation obj)
    {
        continuation();
    }
}

public static class ExtensionMethods
{
    public static UnityWebRequestAwaiter GetAwaiter(this UnityWebRequestAsyncOperation asyncOp)
    {
        return new UnityWebRequestAwaiter(asyncOp);
    }
}

■呼び出し方

public async Task abc()
{

    WWWForm form = new WWWForm();
    UnityWebRequest www = UnityWebRequest.Post("URL", form);

    await www.SendWebRequest();

    var response = www.downloadHandler.text;

}

    public class TestData
    {
        public int aaaa;
        public long bbbb;
        public string cccc;
    }

    public async Task<TestData> Abc()
    {
        TestData ddd = new TestData();


        WWWForm form = new WWWForm();

        // URLはAPIを参照
        UnityWebRequest www = UnityWebRequest.Post("URL", form);

        await www.SendWebRequest();

        var response = www.downloadHandler.text;

       // レスポンスからdddにJsonから変換してデータを入れる。

        return ddd;

    }

■検索参考サイト
https://www.slideshare.net/UnityTechnologiesJapan/unite-tokyo-2018asyncawait
https://stackoverflow.com/questions/55489885/post-json-string-to-webapi-from-unity-c-httpclient-or-unitywebrequest
http://light11.hatenadiary.com/entry/2019/03/07/003356
https://qiita.com/mounntainn/items/3f39e0c57412c48508bf