Delphi 调用C# DLL(包含委托)

例子

C# Dll:

using System;
using System.Collections.Generic;
using System.Text;
using System.Diagnostics;

using System.Runtime.InteropServices;

public delegate void ProcessDelegate(long ptr, long len);

namespace TestDll
{

   public interface ITestClass2
   {

       void YourProcedure();
       void SetDelegate(long ptr);
   }

   [ClassInterface(ClassInterfaceType.None)]
   public class Class2 : ITestClass2
   {
       private ProcessDelegate delProcess = null;

       public void YourProcedure()
       {
           Debug.Print("enter");
           if (this.delProcess != null)
           {
               byte[] test = System.Text.Encoding.Default.GetBytes("hello");
               GCHandle hObject = GCHandle.Alloc(test, GCHandleType.Pinned);
               IntPtr pObject = hObject.AddrOfPinnedObject();
               this.delProcess(pObject.ToInt64(), test.Length);
               if (hObject.IsAllocated)
                   hObject.Free();
           }
           Debug.Print("end");
       }

       public void SetDelegate(long ptr)
       {
           IntPtr intPrt = new IntPtr(ptr);
           delProcess = (ProcessDelegate)Marshal.GetDelegateForFunctionPointer(intPrt, typeof(ProcessDelegate));
       }

   }

}

注意的一点 一定要如下设置:

另外, 如果需要导入其他库的话, 项目-->添加引用;

Delphi调用:

首先要注册dll,  命令行至C:WindowsMicrosoft.NETFrameworkv4.0.30319

运行 regasm "你的dll路径名称.dll"

提示注册成功就可以使用这个dll了

uses ComObj;

procedure callBack(swide: Int64; size: Int64); stdcall;
begin
  OutputDebugString(PChar(IntToStr(swide)+':'+ IntToStr(size)));
end;

procedure TForm1.btn1Click(Sender: TObject);
 var aClass: Variant;
begin
  aClass:= CreateOleObject('TestDll.Class2');
  aClass.SetDelegate(Dword(@call));
  aClass.YourProcedure('test');
end;

示例: 下载地址