update file system

Assets/YooAsset/Runtime/FileSystem/Operation/Internal/DefaultDownloadFileOperation.cs

@@ -1,4 +1,5 @@
-using UnityEngine.Networking;
+using UnityEngine;
+using UnityEngine.Networking;
 
 namespace YooAsset
 {
@@ -61,6 +62,24 @@ namespace YooAsset
                 return _mainURL;
         }
 
+        /// <summary>
+        /// 重置请求字段
+        /// </summary>
+        protected void ResetRequestFiled()
+        {
+            // 重置变量
+            _isAbort = false;
+            _latestDownloadBytes = 0;
+            _latestDownloadRealtime = Time.realtimeSinceStartup;
+            DownloadProgress = 0f;
+            DownloadedBytes = 0;
+
+            // 重置计时器
+            if (_tryAgainTimer > 0f)
+                YooLogger.Warning($"Try again download : {_requestURL}");
+            _tryAgainTimer = 0f;
+        }
+
         /// <summary>
         /// 检测请求超时
         /// </summary>