1.微信小程序登录获取用户的openid信息

需要使用AES-128-CBC解密处理

    /// <summary>/// ASE加解密/// </summary>public class AESHelper{/// <summary>/// 秘钥/// </summary>public static string AesKey;/// <summary>/// 16位初始向量/// </summary>public static string AesIV;/// <summary>/// AES解密/// </summary>/// <param name="text"></param>/// <param name="password"></param>/// <param name="iv"></param>/// <returns></returns>public static string AESDecrypt(string text){try{//16进制数据转换成bytebyte[] encryptedData = Convert.FromBase64String(text);  // strToToHexByte(text);RijndaelManaged rijndaelCipher = new RijndaelManaged();rijndaelCipher.Key = Convert.FromBase64String(AesKey); // Encoding.UTF8.GetBytes(AesKey);rijndaelCipher.IV = Convert.FromBase64String(AesIV);// Encoding.UTF8.GetBytes(AesIV);rijndaelCipher.Mode = CipherMode.CBC;rijndaelCipher.Padding = PaddingMode.PKCS7;ICryptoTransform transform = rijndaelCipher.CreateDecryptor();byte[] plainText = transform.TransformFinalBlock(encryptedData, 0, encryptedData.Length);string result = Encoding.Default.GetString(plainText);return result;}catch (Exception ex){throw ex;}}}

测试代码：

AESHelper.AesIV = "r7BXXKkLb8qrSNn05n0qiA==";
AESHelper.AesKey = "tiihtNczf5v6AKRyjwEUhQ==";
string text ="CiyLU1Aw2KjvrjMdj8YKliAjtP4gsMZM" +"QmRzooG2xrDcvSnxIMXFufNstNGTyaGS" +"9uT5geRa0W4oTOb1WT7fJlAC+oNPdbB+" +"3hVbJSRgv+4lGOETKUQz6OYStslQ142d" +"NCuabNPGBzlooOmB231qMM85d2/fV6Ch" +"evvXvQP8Hkue1poOFtnEtpyxVLW1zAo6" +"/1Xx1COxFvrc2d7UL/lmHInNlxuacJXw" +"u0fjpXfz/YqYzBIBzD6WUfTIF9GRHpOn" +"/Hz7saL8xz+W//FRAUid1OksQaQx4CMs" +"8LOddcQhULW4ucetDf96JcR3g0gfRK4P" +"C7E/r7Z6xNrXd2UIeorGj5Ef7b1pJAYB" +"6Y5anaHqZ9J6nKEBvB4DnNLIVWSgARns" +"/8wR2SiRS7MNACwTyrGvt9ts8p12PKFd" +"lqYTopNHR1Vf7XjfhQlVsAJdNiKdYmYV" +"oKlaRv85IfVunYzO0IKXsyl7JCUjCpoG" +"20f0a04COwfneQAGGwd5oa+T8yO5hzuy" +"Db/XcxxmK01EpqOyuxINew==";
string s = AESHelper.AESDecrypt(text);
Console.WriteLine(s);

原文参考：https://www.cnblogs.com/jetz/p/6384809.html

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