diff --git a/src/SKIT.FlurlHttpClient.Wechat.Work/SDK/Finance/InteropServices/FinanceDllLinuxPInvoker.cs b/src/SKIT.FlurlHttpClient.Wechat.Work/SDK/Finance/InteropServices/FinanceDllLinuxPInvoker.cs
index 065bd79e..2ff5d229 100644
--- a/src/SKIT.FlurlHttpClient.Wechat.Work/SDK/Finance/InteropServices/FinanceDllLinuxPInvoker.cs
+++ b/src/SKIT.FlurlHttpClient.Wechat.Work/SDK/Finance/InteropServices/FinanceDllLinuxPInvoker.cs
@@ -11,51 +11,52 @@ namespace SKIT.FlurlHttpClient.Wechat.Work.SDK.Finance.InteropServices
         public static extern IntPtr NewSdk();
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
-        public static extern int Init(IntPtr sdk, string corpId, string secret);
+        public static extern int Init([In] IntPtr sdk, [In] string corpId, [In] string secret);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
-        public static extern int GetChatData(IntPtr sdk, long seq, long limit, string proxy, string passwd, long timeout, IntPtr chatData);
+        public static extern int GetChatData([In] IntPtr sdk, [In] long seq, [In] long limit, [In] string proxy, [In] string passwd, [In] long timeout, [Out] IntPtr chatData);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
-        public static extern int GetMediaData(IntPtr sdk, string indexBuf, string fileId, string proxy, string passwd, long timeout, IntPtr mediaData);
+        public static extern int GetMediaData([In] IntPtr sdk, [In] string indexBuf, [In] string fileId, [In] string proxy, [In] string passwd, [In] long timeout, [Out] IntPtr mediaData);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
-        public static extern int DecryptData(string encryptKey, string encryptMsg, IntPtr msgData);
+        public static extern int DecryptData([In] string encryptKey, [In] string encryptMsg, [Out] IntPtr msgData);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
-        public static extern void DestroySdk(IntPtr sdk);
+        public static extern void DestroySdk([In] IntPtr sdk);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
         public static extern IntPtr NewSlice();
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
-        public static extern void FreeSlice(IntPtr slice);
+        public static extern void FreeSlice([In] IntPtr slice);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
-        public static extern string GetContentFromSlice(IntPtr slice);
+        [return: MarshalAs(UnmanagedType.CustomMarshaler, MarshalTypeRef = typeof(UTF8Marshaler))]
+        public static extern string GetContentFromSlice([In] IntPtr slice);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
-        public static extern int GetSliceLen(IntPtr slice);
+        public static extern int GetSliceLen([In] IntPtr slice);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
         public static extern IntPtr NewMediaData();
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
-        public static extern void FreeMediaData(IntPtr mediaData);
+        public static extern void FreeMediaData([In] IntPtr mediaData);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
-        public static extern string GetOutIndexBuf(IntPtr mediaData);
+        public static extern string GetOutIndexBuf([In] IntPtr mediaData);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
-        public static extern IntPtr GetData(IntPtr mediaData);
+        public static extern IntPtr GetData([In] IntPtr mediaData);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
-        public static extern int GetIndexLen(IntPtr mediaData);
+        public static extern int GetIndexLen([In] IntPtr mediaData);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
-        public static extern int GetDataLen(IntPtr mediaData);
+        public static extern int GetDataLen([In] IntPtr mediaData);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
-        public static extern int IsMediaDataFinish(IntPtr mediaData);
+        public static extern int IsMediaDataFinish([In] IntPtr mediaData);
     }
 }
diff --git a/src/SKIT.FlurlHttpClient.Wechat.Work/SDK/Finance/InteropServices/FinanceDllWindowsPInvoker.cs b/src/SKIT.FlurlHttpClient.Wechat.Work/SDK/Finance/InteropServices/FinanceDllWindowsPInvoker.cs
index bc5c9e3d..1a4abf1d 100644
--- a/src/SKIT.FlurlHttpClient.Wechat.Work/SDK/Finance/InteropServices/FinanceDllWindowsPInvoker.cs
+++ b/src/SKIT.FlurlHttpClient.Wechat.Work/SDK/Finance/InteropServices/FinanceDllWindowsPInvoker.cs
@@ -14,23 +14,23 @@ namespace SKIT.FlurlHttpClient.Wechat.Work.SDK.Finance.InteropServices
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
         [SuppressUnmanagedCodeSecurity]
-        public static extern int Init(IntPtr sdk, string corpId, string secret);
+        public static extern int Init([In] IntPtr sdk, [In] string corpId, [In] string secret);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
         [SuppressUnmanagedCodeSecurity]
-        public static extern int GetChatData(IntPtr sdk, long seq, long limit, string proxy, string passwd, long timeout, IntPtr chatData);
+        public static extern int GetChatData([In] IntPtr sdk, [In] long seq, [In] long limit, [In] string proxy, [In] string passwd, [In] long timeout, [Out] IntPtr chatData);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
         [SuppressUnmanagedCodeSecurity]
-        public static extern int GetMediaData(IntPtr sdk, string indexBuf, string fileId, string proxy, string passwd, long timeout, IntPtr mediaData);
+        public static extern int GetMediaData([In] IntPtr sdk, [In] string indexBuf, [In] string fileId, [In] string proxy, [In] string passwd, [In] long timeout, [Out] IntPtr mediaData);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
         [SuppressUnmanagedCodeSecurity]
-        public static extern int DecryptData(string encryptKey, string encryptMsg, IntPtr msgData);
+        public static extern int DecryptData([In] string encryptKey, [In] string encryptMsg, [Out] IntPtr msgData);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
         [SuppressUnmanagedCodeSecurity]
-        public static extern void DestroySdk(IntPtr sdk);
+        public static extern void DestroySdk([In] IntPtr sdk);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
         [SuppressUnmanagedCodeSecurity]
@@ -38,16 +38,16 @@ namespace SKIT.FlurlHttpClient.Wechat.Work.SDK.Finance.InteropServices
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
         [SuppressUnmanagedCodeSecurity]
-        public static extern void FreeSlice(IntPtr slice);
+        public static extern void FreeSlice([In] IntPtr slice);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
         [SuppressUnmanagedCodeSecurity]
         [return: MarshalAs(UnmanagedType.CustomMarshaler, MarshalTypeRef = typeof(UTF8Marshaler))]
-        public static extern string GetContentFromSlice(IntPtr slice);
+        public static extern string GetContentFromSlice([In] IntPtr slice);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
         [SuppressUnmanagedCodeSecurity]
-        public static extern int GetSliceLen(IntPtr slice);
+        public static extern int GetSliceLen([In] IntPtr slice);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
         [SuppressUnmanagedCodeSecurity]
@@ -55,26 +55,26 @@ namespace SKIT.FlurlHttpClient.Wechat.Work.SDK.Finance.InteropServices
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
         [SuppressUnmanagedCodeSecurity]
-        public static extern void FreeMediaData(IntPtr mediaData);
+        public static extern void FreeMediaData([In] IntPtr mediaData);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
         [SuppressUnmanagedCodeSecurity]
-        public static extern string GetOutIndexBuf(IntPtr mediaData);
+        public static extern string GetOutIndexBuf([In] IntPtr mediaData);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
         [SuppressUnmanagedCodeSecurity]
-        public static extern IntPtr GetData(IntPtr mediaData);
+        public static extern IntPtr GetData([In] IntPtr mediaData);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
         [SuppressUnmanagedCodeSecurity]
-        public static extern int GetIndexLen(IntPtr mediaData);
+        public static extern int GetIndexLen([In] IntPtr mediaData);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
         [SuppressUnmanagedCodeSecurity]
-        public static extern int GetDataLen(IntPtr mediaData);
+        public static extern int GetDataLen([In] IntPtr mediaData);
 
         [DllImport(DLL_NAME, SetLastError = true, CallingConvention = CallingConvention.Cdecl)]
         [SuppressUnmanagedCodeSecurity]
-        public static extern int IsMediaDataFinish(IntPtr mediaData);
+        public static extern int IsMediaDataFinish([In] IntPtr mediaData);
     }
 }