Added null pointer checks && Removed duplicate file existence checks.

Src/Json_Utilities.cpp

@@ -407,10 +407,12 @@ std::string JsonFile_Parse(const char *path_to_file, Json_Value *pJson_Value)
     if (!err_str.empty())
         return err_str;
 
-    // 尝试打开文件
+    // 检查空指针
+    if (pJson_Value == nullptr)
+        return "Null container ptr.";
+
+    // 打开已完成检查的文件
     FILE *pFile = fopen(path_to_file, "rb");
-    if (pFile == nullptr)
-        return "file \"" + std::string(path_to_file) + "\" open failed.";
 
     // 跳过空白部分 return -> skip count
     auto Lambda_skip_blank = [&](void) -> size_t