C# 调用 c++ dll 的一些问题总结

1.c++的到处函数只要在函数申明的时候加个导出关键字就可以了



2.参数类型问题,

一般的c++中char * 对应 c#中的string

而c++中 char **类型的参数对应c#中 ref string 这种一般都是用来返回字符串的!



3.函数入口问题,一般会出现 "找不到入口点" 这个问题不是由你引起的,而是系统自己把名字改了,改成什么样的名字建议你用eXeScope 打开dll看看里面的全称,比如我从网上下载的一个dll的导出方法列表

导出, CryptoPP32.dll
序列 地址 名字
00000001 100489D0 ?Base64DecodeFile@CryptoPP32@@YA_NPBD0@Z
00000002 1004FAC0 ?Base64DecodeString@CryptoPP32@@YA_NPBDPAPAD@Z
00000003 100488E0 ?Base64EncodeFile@CryptoPP32@@YA_NPBD0@Z
00000004 1004F960 ?Base64EncodeString@CryptoPP32@@YA_NPBDPAPAD@Z
00000005 10045EB0 ?FreeString@CryptoPP32@@YAXPAD@Z
00000006 10048800 ?GunzipFile@CryptoPP32@@YA_NPBD0@Z
00000007 10048720 ?GzipFile@CryptoPP32@@YA_NPBD0H@Z
00000008 10048E30 ?HMAC_SHA1_DecryptFile@CryptoPP32@@YA_NPBD00@Z
00000009 10048B90 ?HMAC_SHA1_DecryptString@CryptoPP32@@YA_NPBD0PAPAD@Z
0000000A 10048D40 ?HMAC_SHA1_EncryptFile@CryptoPP32@@YA_NPBD00@Z
0000000B 1004B540 ?HMAC_SHA1_EncryptString@CryptoPP32@@YA_NPBD0PAPAD@Z
0000000C 10048AB0 ?HexDecodeFile@CryptoPP32@@YA_NPBD0@Z
0000000D 1004FE10 ?HexDecodeString@CryptoPP32@@YA_NPBDPAPAD@Z
0000000E 1004B3D0 ?HexEncodeFile@CryptoPP32@@YA_NPBD0@Z
0000000F 1004FC20 ?HexEncodeString@CryptoPP32@@YA_NPBDPAPAD@Z
00000010 1004C260 ?RSAES_OAEP_DecryptString2@CryptoPP32@@YA_NPBD0PAPAD@Z
00000011 1004CD60 ?RSAES_OAEP_DecryptString@CryptoPP32@@YA_NPBD00000000PAPAD@Z
00000012 1004C4C0 ?RSAES_OAEP_DecryptString@CryptoPP32@@YA_NPBD0PAPAD@Z
00000013 1004B780 ?RSAES_OAEP_EncryptString2@CryptoPP32@@YA_NPBD0PAPAD0@Z
00000014 1004C790 ?RSAES_OAEP_EncryptString@CryptoPP32@@YA_NPBD00PAPAD0@Z
00000015 1004BCF0 ?RSAES_OAEP_EncryptString@CryptoPP32@@YA_NPBD0PAPAD0@Z
00000016 10049220 ?RSAES_OAEP_GenKeyFiles@CryptoPP32@@YA_NPBD0I0@Z
00000017 100498E0 ?RSAES_OAEP_GenKeyStrings@CryptoPP32@@YA_NPAPAD0IPBD@Z
00000018 1004DDB0 ?RSAES_PKCS_DecryptString2@CryptoPP32@@YA_NPBD0PAPAD@Z
00000019 1004E870 ?RSAES_PKCS_DecryptString@CryptoPP32@@YA_NPBD00000000PAPAD@Z
0000001A 1004E010 ?RSAES_PKCS_DecryptString@CryptoPP32@@YA_NPBD0PAPAD@Z
0000001B 1004D2D0 ?RSAES_PKCS_EncryptString2@CryptoPP32@@YA_NPBD0PAPAD0@Z
0000001C 1004E2E0 ?RSAES_PKCS_EncryptString@CryptoPP32@@YA_NPBD00PAPAD0@Z
0000001D 1004D840 ?RSAES_PKCS_EncryptString@CryptoPP32@@YA_NPBD0PAPAD0@Z
0000001E 1004A070 ?RSAES_PKCS_GenKeyFiles@CryptoPP32@@YA_NPBD0I0@Z
0000001F 1004A730 ?RSAES_PKCS_GenKeyStrings@CryptoPP32@@YA_NPAPAD0IPBD@Z
00000020 1004AEC0 ?RSASS_PKCS_SignFile@CryptoPP32@@YA_NPBD000@Z
00000021 1004EDE0 ?RSASS_PKCS_SignString@CryptoPP32@@YA_NPBD0PAPAD0@Z
00000022 100481D0 ?RSASS_PKCS_VerifyFile@CryptoPP32@@YA_NPBD000@Z
00000023 1004F380 ?RSASS_PKCS_VerifyString@CryptoPP32@@YA_NPBD000@Z

比如我要用 RSAES_PKCS_EncryptString这个方法,但是已经不能这么用了

应该改成下面的方法

using System.Runtime.InteropServices;
namespace KSN.BLL.Common
{
    public class RSACrypt
    {
        /// <summary>
        /// 获取密钥文件
        /// </summary>
        /// <param name="privFilename">私钥文件路径</param>
        /// <param name="pubFilename">公文文件路径</param>
        /// <param name="keyLength">密钥长度</param>
        /// <param name="seed">随机种子</param>
        /// <returns></returns>
        [DllImport("CryptoPP32.dll",
            EntryPoint = "RSAES_PKCS_GenKeyFiles",
            CharSet = CharSet.Ansi)]
        private static extern bool RSAES_PKCS_GenKeyFiles( string privFilename,  string pubFilename, int keyLength,  string seed);

        /// <summary>
        /// 获取字符串形式的密钥
        /// </summary>
        /// <param name="outPrivKey">私钥</param>
        /// <param name="outPubKey">公钥</param>
        /// <param name="keyLength">密钥长度</param>
        /// <param name="seed">随机种子</param>
        /// <returns></returns>
        [DllImport("CryptoPP32.dll", EntryPoint = "?RSAES_PKCS_GenKeyStrings@CryptoPP32@@YA_NPAPAD0IPBD@Z", CharSet = CharSet.Ansi, CallingConvention = CallingConvention.StdCall)]
        public static extern bool RSAES_PKCS_GenKeyStrings(ref string outPrivKey, ref string outPubKey, int keyLength,  string seed);
        
        /// <summary>
        /// RSA加密字符串
        /// </summary>
        /// <param name="strPubKey">公钥</param>
        /// <param name="message">被加密信息</param>
        /// <param name="outCipher">加密后密文</param>
        /// <param name="seed">随机种子</param>
        /// <returns></returns>
        [DllImport("CryptoPP32.dll", EntryPoint = "?RSAES_PKCS_EncryptString@CryptoPP32@@YA_NPBD0PAPAD0@Z", CharSet = CharSet.Ansi, CallingConvention = CallingConvention.StdCall)]
        public static extern bool RSAES_PKCS_EncryptString( string strPubKey,  string message, ref string outCipher,  string seed);
         
        //[DllImport("CryptoPP32.dll")]
        //private static extern bool RSAES_PKCS_EncryptString( string N, string E,  string message, ref string outCipher,  string seed);

        //[DllImport("CryptoPP32.dll")]
        //private static extern bool RSAES_PKCS_EncryptString2(ref string pubFilename, ref string message, ref string outCipher,  string seed);

        /// <summary>
        /// RSA解密字符串
        /// </summary>
        /// <param name="strPrivKey">私钥</param>
        /// <param name="cipher">密文</param>
        /// <param name="outPlain">解密后的原文</param>
        /// <returns></returns>
        [DllImport("CryptoPP32.dll", EntryPoint = "?RSAES_PKCS_DecryptString@CryptoPP32@@YA_NPBD0PAPAD@Z", CharSet = CharSet.Ansi, CallingConvention = CallingConvention.StdCall)]
        public static extern bool RSAES_PKCS_DecryptString( string strPrivKey,  string cipher, ref string outPlain);

        //[DllImport("CryptoPP32.dll")]
        //private static extern bool RSAES_PKCS_DecryptString( string N,  string E,  string D,  string P,  string Q,  string dP,  string dQ,  string U,  string cipher, ref string outPlain);

        //[DllImport("CryptoPP32.dll")]
        //private static extern bool RSAES_PKCS_DecryptString2( string privFilename,  string cipher, ref string outPlain);

    }
}