C# 動態載入 AppDomain 實作（二）：RemoteLoader 代理類別與跨域方法呼叫

2、建立 RemoteLoader 類別

它可在 AppDomain 間自由穿梭，故需繼承 System.MarshalByRefObject 抽象類別。若不繼承，在不同 AppDomain 傳遞物件時必會報錯（跨域傳遞的物件必須可序列化）。以 RemoteLoader 做為代理呼叫待執行的 .NET 程式。

using System;
using System.Collections.Generic;
using System.Globalization;
using System.IO;
using System.Reflection;
using System.Text;

/// <summary> The Remote loader. </summary>
public class RemoteLoader : MarshalByRefObject
{
    private Assembly assembly = null;
    private String output = String.Empty;

    public String Output { get { return this.output; } }

    /// <summary> 呼叫目標方法 </summary>
    public void InvokeMethod(String fullName, String className, String argsInput, String programName)
    {
        this.assembly = null; this.output = String.Empty;
        try
        {
            this.assembly = Assembly.LoadFrom(fullName);
            Type pgmType = null;
            if (this.assembly != null) pgmType = this.assembly.GetType(className, true, true);
            else pgmType = Type.GetType(className, true, true);

            Object[] args = RunJob.GetArgs(argsInput);
            BindingFlags defaultBinding = BindingFlags.DeclaredOnly | BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.IgnoreCase | BindingFlags.InvokeMethod | BindingFlags.Static;
            CultureInfo cultureInfo = new CultureInfo("es-ES", false);

            try
            {
                MethodInfo methisInfo = RunJob.GetItsMethodInfo(pgmType, defaultBinding, programName);
                if (methisInfo == null) { this.output = "EMethod does not exist!"; }

                if (methisInfo.IsStatic)
                {
                    if (methisInfo.GetParameters().Length == 0)
                    {
                        if (methisInfo.ReturnType == typeof(void)) { pgmType.InvokeMember(programName, defaultBinding, null, null, null, cultureInfo); this.output = "STo call a method without return value successful."; }
                        else { this.output = (String)pgmType.InvokeMember(programName, defaultBinding, null, null, null, cultureInfo); }
                    }
                    else
                    {
                        if (methisInfo.ReturnType == typeof(void)) { pgmType.InvokeMember(programName, defaultBinding, null, null, args, cultureInfo); this.output = "STo call a method without return value successful."; }
                        else { this.output = (String)pgmType.InvokeMember(programName, defaultBinding, null, null, args, cultureInfo); }
                    }
                }
                else
                {
                    if (methisInfo.GetParameters().Length == 0)
                    {
                        object pgmClass = Activator.CreateInstance(pgmType);
                        if (methisInfo.ReturnType == typeof(void)) { pgmType.InvokeMember(programName, defaultBinding, null, pgmClass, null, cultureInfo); this.output = "STo call a method without return value successful."; }
                        else { this.output = (String)pgmType.InvokeMember(programName, defaultBinding, null, pgmClass, null, cultureInfo); }
                    }
                    else
                    {
                        object pgmClass = Activator.CreateInstance(pgmType);
                        if (methisInfo.ReturnType == typeof(void)) { pgmType.InvokeMember(programName, defaultBinding, null, pgmClass, args, cultureInfo); this.output = "STo call a method without return value successful."; }
                        else { this.output = (String)pgmType.InvokeMember(programName, defaultBinding, null, pgmClass, args, cultureInfo); }
                    }
                }
            }
            catch { this.output = (String)pgmType.InvokeMember(programName, defaultBinding, null, null, null, cultureInfo); }
        }
        catch (Exception e) { this.output = "E" + e.Message; }
    }
}

InvokeMethod 方法只需提供組件全名、類別全名、待執行方法的輸入參數與全名即可執行，支援帶參數/不帶參數、靜態/非靜態方法。

使用方式

AssemblyDynamicLoader loader = new AssemblyDynamicLoader();
String output = loader.InvokeMethod("fileName", "ymtcla", "yjoinp", "ymtpgm");
loader.Unload();