diff --git a/vault-decryptFile/Program.cs b/vault-decryptFile/Program.cs
index 1bc52a6..0933ec8 100644
--- a/vault-decryptFile/Program.cs
+++ b/vault-decryptFile/Program.cs
@@ -1 +1,83 @@
-Console.WriteLine("Hello, World!");
+using System.Security.Cryptography;
+using System.Text;
+
+class Program
+{
+    static void Main(string[] args)
+    {
+        if (args.Length != 5)
+        {
+            Console.WriteLine("Usage: .exe <operate[dec,enc]> <inputFilePath> <outputFilePath> <password> <salt>");
+            return;
+        }
+        string operate = args[0];
+        string inputFilePath = args[1];
+        string outputFilePath = args[2];
+        string password = args[3];
+        string salt = args[4];
+        if(operate == "dec")
+        {
+            byte[] inputData = File.ReadAllBytes(inputFilePath);
+            byte[] outputData = DecryptFile(inputData, password, salt);
+
+            File.WriteAllBytes(outputFilePath, outputData);
+        }
+        else if(operate == "enc")
+        {
+            byte[] inputData = File.ReadAllBytes(inputFilePath);
+            byte[] outputData = EncryptFile(inputData, password, salt);
+
+            File.WriteAllBytes(outputFilePath, outputData);
+        }
+        else
+        {
+            Console.WriteLine("Usage: .exe <operate[dec,enc]> <inputFilePath> <outputFilePath> <password> <salt>");
+            return;
+        }
+
+    }
+
+    public static byte[] DecryptFile(byte[] encryptedData, string password, string salt)
+    {
+        byte[] passwordBytes = Encoding.UTF8.GetBytes(password);
+        byte[] saltBytes = Encoding.UTF8.GetBytes(salt);
+        using (var pbkdf2 = new Rfc2898DeriveBytes(passwordBytes, saltBytes, 100000, HashAlgorithmName.SHA256))
+        {
+            byte[] key = pbkdf2.GetBytes(32);
+            byte[] iv = new byte[12];
+            Array.Copy(encryptedData, 0, iv, 0, 12);
+            byte[] tag = new byte[16];
+            Array.Copy(encryptedData, encryptedData.Length - 16, tag, 0, 16);
+            byte[] ciphertext = new byte[encryptedData.Length - 28];
+            Array.Copy(encryptedData, 12, ciphertext, 0, ciphertext.Length);
+            byte[] plaintext = new byte[ciphertext.Length];
+            using (var aes = new AesGcm(key,16))
+            {
+                aes.Decrypt(iv, ciphertext, tag, plaintext);
+            }
+            return plaintext;
+        }
+    }
+
+    public static byte[] EncryptFile(byte[] plaintextData, string password, string salt)
+    {
+        byte[] passwordBytes = Encoding.UTF8.GetBytes(password);
+        byte[] saltBytes = Encoding.UTF8.GetBytes(salt);
+        using (var pbkdf2 = new Rfc2898DeriveBytes(passwordBytes, saltBytes, 100000, HashAlgorithmName.SHA256))
+        {
+            byte[] key = pbkdf2.GetBytes(32);
+            byte[] iv = new byte[12];
+            using (var rng = RandomNumberGenerator.Create())
+            {
+                rng.GetBytes(iv);
+            }
+            byte[] ciphertext = new byte[plaintextData.Length];
+            byte[] tag = new byte[16];
+            using (var aes = new AesGcm(key,16))
+            {
+                aes.Encrypt(iv, plaintextData, ciphertext, tag);
+            }
+            return [.. iv, .. ciphertext, .. tag];
+        }
+    }
+}
\ No newline at end of file
diff --git a/vault-decryptFile/vault-decryptFile.csproj b/vault-decryptFile/vault-decryptFile.csproj
index f2f8a68..1c3590d 100644
--- a/vault-decryptFile/vault-decryptFile.csproj
+++ b/vault-decryptFile/vault-decryptFile.csproj
@@ -2,10 +2,19 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net8.0</TargetFramework>
+    <TargetFramework>net8.0-windows10.0.22621.0</TargetFramework>
     <RootNamespace>vault_decryptFile</RootNamespace>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
+    <SupportedOSPlatformVersion>7.0</SupportedOSPlatformVersion>
+  </PropertyGroup>
+
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">
+    <DebugType>embedded</DebugType>
+  </PropertyGroup>
+
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|AnyCPU'">
+    <DebugType>embedded</DebugType>
   </PropertyGroup>
 
 </Project>