diff --git a/Assets/YooAsset/Runtime/DownloadSystem/Requester/AssetBundleWebRequest.cs b/Assets/YooAsset/Runtime/DownloadSystem/Requester/AssetBundleWebRequest.cs
index 4edc3c5..234f7d8 100644
--- a/Assets/YooAsset/Runtime/DownloadSystem/Requester/AssetBundleWebRequest.cs
+++ b/Assets/YooAsset/Runtime/DownloadSystem/Requester/AssetBundleWebRequest.cs
@@ -17,6 +17,7 @@ namespace YooAsset
 		public string RequestNetError { private set; get; }
 		public long RequestHttpCode { private set; get; }
 
+		public AssetBundleWebRequest() { }
 		public void Create(string requestURL, BundleInfo bundleInfo, params object[] args)
 		{
 			if (Status != ERequestStatus.None)
diff --git a/Assets/YooAsset/Runtime/DownloadSystem/Requester/FileGeneralRequest.cs b/Assets/YooAsset/Runtime/DownloadSystem/Requester/FileGeneralRequest.cs
index 0d0904d..0838f53 100644
--- a/Assets/YooAsset/Runtime/DownloadSystem/Requester/FileGeneralRequest.cs
+++ b/Assets/YooAsset/Runtime/DownloadSystem/Requester/FileGeneralRequest.cs
@@ -12,7 +12,8 @@ namespace YooAsset
 		public ulong DownloadedBytes { private set; get; }
 		public string RequestNetError { private set; get; }
 		public long RequestHttpCode { private set; get; }
-
+		
+		public FileGeneralRequest() { }
 		public void Create(string requestURL, BundleInfo bundleInfo, params object[] args)
 		{
 			if (Status != ERequestStatus.None)
diff --git a/Assets/YooAsset/Runtime/DownloadSystem/Requester/FileResumeRequest.cs b/Assets/YooAsset/Runtime/DownloadSystem/Requester/FileResumeRequest.cs
index 5eb27d6..d04d8ce 100644
--- a/Assets/YooAsset/Runtime/DownloadSystem/Requester/FileResumeRequest.cs
+++ b/Assets/YooAsset/Runtime/DownloadSystem/Requester/FileResumeRequest.cs
@@ -8,14 +8,15 @@ namespace YooAsset
 		private string _tempFilePath;
 		private UnityWebRequest _webRequest;
 		private DownloadHandlerFileRange _downloadHandle;
-		private ulong _fileOriginLength;
+		private ulong _fileOriginLength = 0;
 
 		public ERequestStatus Status { private set; get; } = ERequestStatus.None;
 		public float DownloadProgress { private set; get; }
 		public ulong DownloadedBytes { private set; get; }
 		public string RequestNetError { private set; get; }
 		public long RequestHttpCode { private set; get; }
-
+		
+		public FileResumeRequest() { }
 		public void Create(string requestURL, BundleInfo bundleInfo, params object[] args)
 		{
 			if (Status != ERequestStatus.None)