[Pull Request] KXP文件增加格式识别头

KitX File Format Helper/KitX.KXP.Helper/Decoder.cs

@@ -46,10 +46,19 @@ public string Decode(string releaseFolder)
 
             byte[] src = File.ReadAllBytes(PackagePath);    //  读取包的全部字节
 
-            int cursor = 0;     //  文件流指针
+            byte[] header = new byte[16];
 
-            for (; cursor < 16; ++cursor)       //  取出哈希部分的字节
-                hash[cursor] = src[cursor];
+            for(int i = 0; i < 16; ++ i)
+                header[i] = src[i];
+
+            for (int i = 0; i < 16; ++i)
+                if (header[i] != Header.header[i])
+                    throw new Exception("It's not a KXP Package.");
+
+            int cursor = 16;     //  文件流指针
+
+            for (; cursor < 32; ++cursor)       //  取出哈希部分的字节
+                hash[cursor - 16] = src[cursor];
 
 #if DEBUG
             Console.WriteLine($"Hash Code: {Encoding.UTF8.GetString(hash)}");
@@ -131,7 +140,7 @@ public string Decode(string releaseFolder)
 
             MD5 md5 = MD5.Create();
 
-            byte[] localHash = md5.ComputeHash(src, 16, src.Length - 16);
+            byte[] localHash = md5.ComputeHash(src, 32, src.Length - 32);
 
             md5.Dispose();
 

KitX File Format Helper/KitX.KXP.Helper/Encoder.cs

@@ -111,6 +111,11 @@ public void Encode(string rootDir, string saveFolder, string filename)
             Console.Write($"Hash Code: {Encoding.UTF8.GetString(hash)}");
 #endif
 
+            foreach (var item in Header.header)
+            {
+                fs.WriteByte(item);     //  写入文件标头
+            }
+
             foreach (var item in hash)
             {
                 fs.WriteByte(item);     //  写入哈希值

KitX File Format Helper/KitX.KXP.Helper/Header.cs

@@ -0,0 +1,26 @@
+namespace KitX.KXP.Helper
+{
+    internal static class Header
+    {
+        public static byte[] header = new byte[16]
+        {
+            110,    //  n
+            105,    //  i
+            100,    //  d
+            117,    //  u
+            111,    //  o
+            106,    //  j
+            105,    //  i
+            117,    //  u
+            104,    //  h
+            117,    //  u
+            105,    //  i
+            108,    //  l
+            097,    //  a
+            105,    //  i
+            097,    //  a
+            063,    //  ?
+        };
+
+    }
+}