Update YooAsset

Assets/YooAsset/Runtime/OperationSystem/AsyncOperationBase.cs

@@ -0,0 +1,71 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+
+namespace YooAsset
+{
+	public abstract class AsyncOperationBase : IEnumerator
+	{
+		/// <summary>
+		/// 状态
+		/// </summary>
+		public EOperationStatus Status { get; protected set; } = EOperationStatus.None;
+
+		/// <summary>
+		/// 错误信息
+		/// </summary>
+		public string Error { get; protected set; } = string.Empty;
+
+		/// <summary>
+		/// 是否已经完成
+		/// </summary>
+		public bool IsDone
+		{
+			get
+			{
+				return Status == EOperationStatus.Failed || Status == EOperationStatus.Succeed;
+			}
+		}
+
+		/// <summary>
+		/// 用户请求的回调
+		/// </summary>
+		private Action<AsyncOperationBase> _callback;
+
+		/// <summary>
+		/// 完成事件
+		/// </summary>
+		public event Action<AsyncOperationBase> Completed
+		{
+			add
+			{
+				if (IsDone)
+					value.Invoke(this);
+				else
+					_callback += value;
+			}
+			remove
+			{
+				_callback -= value;
+			}
+		}
+
+		internal abstract void Start();
+		internal abstract void Update();
+		internal void Finish()
+		{
+			_callback?.Invoke(this);
+		}
+
+		#region 异步相关
+		public bool MoveNext()
+		{
+			return !IsDone;
+		}
+		public void Reset()
+		{
+		}
+		public object Current => null;
+		#endregion
+	}
+}