最近一個同事問我，他想實現在瀏覽器輸入一個url，執行某個dll中的方法。

這個url的規則很簡單：https://localhost:8080/名稱空間/類名/方法名?param1=2&param2=3.3

遇到這種問題，毫不猶豫，上反射。

        /// <summary>
        /// 解析標準的url，通過反射呼叫對應的名稱空間.類.方法
        /// </summary>
        /// <param name="url"></param>
        /// <param name="dllPath"></param>
 

        public void ResolveUrlAndExcute(string url, string dllPath)
        {
            //https://localhost:8080/ClassLibrary1/MyClass/MyMethods?a=2&b=3.3
            url = url.Replace("https://localhost:8080/", "");
            string[] arr1 = url.Split("?");
            string[] arr2 = arr1[0].Split("/");
            
 
string typeName = arr2[0] + "." + arr2[1];
            string methodName = arr2[2];

            List<object> listParameters = new List<object>();
            string[] arr3 = arr1[1].Split("&");
            foreach(string param in arr3)
            {
                listParameters.Add((
 
object)param.Split("=")[1]);
            }

            var assembly = Assembly.LoadFile(dllPath);
            Type type = assembly.GetType(typeName);// namespace.class
            if(type != null)
            {
                MethodInfo methodInfo = type.GetMethod(methodName);// method name
                if(methodInfo != null)
                {
                    object result = null;
                    ParameterInfo[] parameters = methodInfo.GetParameters();
                    object classInstance = Activator.CreateInstance(type, null);

                    if(parameters.Length == 0)
                    {
                        result = methodInfo.Invoke(classInstance, null);
                    }
                    else
                    {
                        result = methodInfo.Invoke(classInstance, listParameters.ToArray());
                    }
                }
            }
        }

如果想反向，把每一個方法轉成標準的url，就更簡單了。

        /// <summary>
        /// 把dll中的方法通過反射轉換成url
        /// </summary>
        /// <param name="dllPath"></param>
        /// <returns></returns>
        public static List<string> ComposeRequestUrl(string dllPath)
        {
            List<string> urls = new List<string>();

            var assembly = Assembly.LoadFile(dllPath);
            foreach (var type in assembly.GetTypes())
            {
                string baseUrl = "https://localhost:8080/" + type.Namespace + "/" + type.Name + "/";

                MethodInfo[] myArrayMethodInfo = type.GetMethods(BindingFlags.Public | BindingFlags.Static | BindingFlags.Instance | BindingFlags.DeclaredOnly);

                foreach (var methodInfo in myArrayMethodInfo)
                {
                    string url = baseUrl + methodInfo.Name + "?";
                    string retVal = string.Empty;
                    if (methodInfo != null)
                    {
                        var parameters = methodInfo.GetParameters();
                        foreach (var param in parameters)
                        {
                            url += param.Name + "=&";
                        }
                    }

                    Debug.WriteLine(url.Substring(0, url.Length - 1));
                    urls.Add(url.Substring(0, url.Length - 1));
                }
            }

            return urls;
        }