Question

我在以下代码中的VS Code（在Ubuntu上运行）中出现错误

class Program
{
    public static void Main()
    {
        string originalText = "Test";

        try
        {
            using (Aes myAes = new Aes.Create())
            {

                string encrypted = StringCipher.Encrypt(originalText, myAes);
                string decrypted = StringCipher.Decrypt(encrypted, myAes);

                Console.WriteLine(String.Format("Original {0}", originalText));
                Console.WriteLine(String.Format("Encrypted {0}", encrypted));
                Console.WriteLine(String.Format("Decrypted {0}", decrypted));

            }
        }
        catch (Exception e)
        {
            Console.WriteLine(e.Message);
        }
        Console.ReadKey();
    }
}

VS Code intellisense声明类型名称＆＃39;创建＆＃39;在Aes类型中不存在。

不确定这是不是我的错误编码，但我基本上遵循指南here。

我实现加密/解密的唯一区别是在一个单独的代码文件中实现：

using System;
using System.Text;
using System.Security.Cryptography;
using System.IO;
using System.Linq;

namespace EncryptionConsole
{
    public static class StringCipher
    {

        public static string Encrypt(string plainText, Aes aes)
        {

                    // Encrypt the string to an array of bytes.
                    byte[] encrypted = EncryptStringToBytes_Aes(plainText, aes.Key, aes.IV);
                    string result = Encoding.UTF8.GetString(encrypted);
                    return result;

        }

        public static string Decrypt(string cipherText, Aes aes)
        {
            byte[] cipherTextArray = Encoding.UTF8.GetBytes(cipherText); 

                // Decrypt the bytes to a string.
                string roundtrip = DecryptStringFromBytes_Aes(cipherTextArray, aes.Key, aes.IV);
                return roundtrip;
        }

        static byte[] EncryptStringToBytes_Aes(string plainText, byte[] Key, byte[] IV)
        {
            // Check arguments.
            if (plainText == null || plainText.Length <= 0)
                throw new ArgumentNullException("plainText");
            if (Key == null || Key.Length <= 0)
                throw new ArgumentNullException("Key");
            if (IV == null || IV.Length <= 0)
                throw new ArgumentNullException("IV");
            byte[] encrypted;
            // Create an Aes object
            // with the specified key and IV.
            using (Aes aesAlg = Aes.Create())
            {
                aesAlg.Key = Key;
                aesAlg.IV = IV;

                // Create a decrytor to perform the stream transform.
                ICryptoTransform encryptor = aesAlg.CreateEncryptor(aesAlg.Key, aesAlg.IV);

                // Create the streams used for encryption.
                using (MemoryStream msEncrypt = new MemoryStream())
                {
                    using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
                    {
                        using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))
                        {

                            //Write all data to the stream.
                            swEncrypt.Write(plainText);
                        }
                        encrypted = msEncrypt.ToArray();
                    }
                }
            }

            // Return the encrypted bytes from the memory stream.
            return encrypted;
        }

        static string DecryptStringFromBytes_Aes(byte[] cipherText, byte[] Key, byte[] IV)
        {
            // Check arguments.
            if (cipherText == null || cipherText.Length <= 0)
                throw new ArgumentNullException("cipherText");
            if (Key == null || Key.Length <= 0)
                throw new ArgumentNullException("Key");
            if (IV == null || IV.Length <= 0)
                throw new ArgumentNullException("IV");

            // Declare the string used to hold
            // the decrypted text.
            string plaintext = null;

            // Create an Aes object
            // with the specified key and IV.
            using (Aes aesAlg = Aes.Create())
            {
                aesAlg.Key = Key;
                aesAlg.IV = IV;

                // Create a decrytor to perform the stream transform.
                ICryptoTransform decryptor = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV);

                // Create the streams used for decryption.
                using (MemoryStream msDecrypt = new MemoryStream(cipherText))
                {
                    using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
                    {
                        using (StreamReader srDecrypt = new StreamReader(csDecrypt))
                        {

                            // Read the decrypted bytes from the decrypting stream
                            // and place them in a string.
                            plaintext = srDecrypt.ReadToEnd();
                        }
                    }
                }

            }

            return plaintext;

        }

    }
}

我很欣赏上面代码中可能存在一些明显的错误，这不是我真正关心的问题，因为我现在正在探索。

非常感谢任何帮助。

Answer 1

Aes.Create()是一种静态方法。您无需使用关键字new进行实例化。如果你查看文档（https://msdn.microsoft.com/en-us/library/bb351532(v=vs.110).aspx），你会发现这个方法实际上为你返回了一个新创建的AES对象。这在编程术语中称为“静态工厂方法”，是初始化对象的常用做法/模式。

Answer 2

Basically calling Aes myAes = new Aes.Create() will try to instanciate the class Create from the namespace or class Aes which explains the error you experience. As stated above you can just use Aes myAes = Aes.Create().

类型名称＆＃39;创建＆＃39; Aes

2 个答案: