C#與vb6 com組件的互相調用方法

1.首先在vs2008中，新建項目選擇c#項目->類庫

  編寫一下代碼

using System;
using System.IO;
using System.Text;
using System.Security.Cryptography;
using System.Runtime.InteropServices;

namespace JCCT.Security
{
    /*應用於VB6的dll調用*/
   
        //首先建立接口，這個是Com必須使用的
    [ComVisible(true)]
    [Guid("4B6FD86C-B096-4e6a-AC7F-442A51FA0776")]
        public interface IEncrypt
        {
            string AESEncrypt(string plainStr);
            string AESDecrypt(string encryptStr);
        }

        //寫接口的實現
    [ComVisible(true)]
    [Guid("367BF149-DBB3-4184-9A5C-978CC8C10787")]
    [ProgId("ClassLibrary1.AES")]
        public class AES : IEncrypt
        {

            /// <summary>
            /// 獲取密鑰
            /// </summary>
            private static string Key
            {
                get { return @"HJ(S<?l78242^&WL%#jCD8dkiI39(euw"; }
            }

            /// <summary>
            /// 獲取向量
            /// </summary>
            private static string IV
            {
                get { return @"mailto:L@uDe4Kf&amp;amp;amp;amp;amp;#^j8E53"; }
            }

            /// <summary>
            /// AES加密
            /// </summary>
            /// <param name="plainStr">明文字符串</param>
            /// <returns>密文</returns>
            public string AESEncrypt(string plainStr)
            {
                byte[] bKey = Encoding.UTF8.GetBytes(Key);
                byte[] bIV = Encoding.UTF8.GetBytes(IV);
                byte[] byteArray = Encoding.UTF8.GetBytes(plainStr);

                string encrypt = null;
                Rijndael aes = Rijndael.Create();
                try
                {
                    using (MemoryStream mStream = new MemoryStream())
                    {
                        using (CryptoStream cStream = new CryptoStream(mStream, aes.CreateEncryptor(bKey, bIV), CryptoStreamMode.Write))
                        {
                            cStream.Write(byteArray, 0, byteArray.Length);
                            cStream.FlushFinalBlock();
                            encrypt = Convert.ToBase64String(mStream.ToArray());
                        }
                    }
                }
                catch { }
                aes.Clear();

                return encrypt;
            }

            /// <summary>
            /// AES解密
            /// </summary>
            /// <param name="encryptStr">密文字符串</param>
            /// <returns>明文</returns>
            public string AESDecrypt(string encryptStr)
            {
                string decrypt = null;
                Rijndael aes = Rijndael.Create();
                try
                {
                    byte[] bKey = Encoding.UTF8.GetBytes(Key);
                    byte[] bIV = Encoding.UTF8.GetBytes(IV);
                    byte[] byteArray = Convert.FromBase64String(encryptStr);
                    using (MemoryStream mStream = new MemoryStream())
                    {
                        using (CryptoStream cStream = new CryptoStream(mStream, aes.CreateDecryptor(bKey, bIV), CryptoStreamMode.Write))
                        {
                            cStream.Write(byteArray, 0, byteArray.Length);
                            cStream.FlushFinalBlock();
                            decrypt = Encoding.UTF8.GetString(mStream.ToArray());
                        }
                    }
                }
                catch
                {
                    decrypt = encryptStr;
                }
                aes.Clear();

                return decrypt;
            }
        }
        
}

2.在文件AssemblyInfo.cs中，設置[assembly: ComVisible(true)]，默認是false的,需要設置成true

 3.選擇項目屬性，在生成標簽卡中，勾選為com互操作注冊.

 4.生成項目dll文件。

  Guid生成:在工具->創建Guid生成，格式選擇第四種，點復制之后需要把兩邊的{}除掉.

 5.注冊.regasm ClassLibrary1.dll /tlb:ClassLibrary1.tlb
如果點項目右鍵屬性：

可以編譯后自動生成tlb,不需要再用vs.net命令生成。注意要以管理員身份運行vs.net.

 

 6.在vb6 中引用ClassLibrary1.tlb文件，注意不是ClassLibrary1.dll文件

引用的話，在vb6編寫時可以看到ClassLibrary1的類的方法。

    Dim obj As Object
    Set obj = CreateObject("ClassLibrary1.AES")
    Form1.Text2.Text = obj.AESDecrypt(Form1.Text1.Text) 

當用VB6生成的應用程序，拷貝到其它機上，又不能運行了，提示：ACTIVEX 不能創建對象。后終於找到解決辦法：
用命令：regasm path +ClassLibrary.dll /tlb:ClassLibrary.tlb /codebase

如果用vb6生成dll文件在c#訪問方法：
方法很簡單 只需要生成dll, 然后在C#中引用就行了。