.Net中关于RijndaelManaged加密算法问题？

[linxi1151]

为什么下面的方法得到的加密串为空？

    private byte[] key = { 24, 55, 102, 24, 56, 26, 67, 29, 84, 19, 37, 118, 104, 85, 178, 27, 93, 86, 24, 55, 102, 24, 98, 26, 67, 29, 9, 2, 49, 69, 73, 92 };
    private byte[] iv =  { 9, 5, 89, 7, 76, 3, 12, 45, 89, 63, 78, 95, 42, 15, 73, 92 };

    public string encriptString(string input)
    {
        string rst = "";        
        if (string.IsNullOrEmpty(input))
        {
            return "";
        }
        byte[] data = Encoding.UTF7.GetBytes(input);
        MemoryStream msOut = new MemoryStream();
        //定义对称算法对象实例和接口

        RijndaelManaged rij = new RijndaelManaged();
        ICryptoTransform transform = rij.CreateEncryptor(key, iv);
        CryptoStream cstream = new CryptoStream(msOut, transform, CryptoStreamMode.Write);
        cstream.Write(data, 0,data.Length);
        StreamReader sr = new StreamReader(msOut);
        rst = sr.ReadToEnd();      
        cstream.FlushFinalBlock();
        cstream.Close();
        msOut.Close();
        sr.Close();
        return rst;
    }

[accpzwt]

public string Md5(string password)
{
MD5CryptoServiceProvider hashmd5 = new MD5CryptoServiceProvider();
//使用加密服务提供程序 (CSP) 提供的实现，计算输入数据的 MD5 哈希值。无法继承此类。
return BitConverter.ToString(hashmd5.ComputeHash(Encoding.Default.GetBytes(password))).Replace("-", "");
//System命名空间BitConverter将基础数据类型与字节数组相互转换。
//GetBytes将指定的数据转换为字节数组。
//ComputeHash计算输入数据的哈希值的方法。
}

[accpzwt]

回答错了，嘿嘿，一般我的MD5就是用我的这个方法写的。

[John_Yang]

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("Key");

// Declare the stream used to encrypt to an in memory
// array of bytes.
MemoryStream msEncrypt = null;

// Declare the RijndaelManaged object
// used to encrypt the data.
RijndaelManaged aesAlg = null;

try
{
// Create a RijndaelManaged object
// with the specified key and IV.
aesAlg = new RijndaelManaged();
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.
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);
}
}

}
finally
{

// Clear the RijndaelManaged object.
if (aesAlg != null)
aesAlg.Clear();
}

// Return the encrypted bytes from the memory stream.
return msEncrypt.ToArray();

}

[John_Yang]

你的代码问题在于CryptoStream对象在Write后没有Close,所以并没有执行加密算法，
应该在cstream.Write(data, 0,data.Length);这句代码后加上cstream.close();


给你看MSDN上面的解释
You should always explicitly close your CryptoStream object after you are done using it by calling the Close method. Doing so flushes the stream and causes all remaining blocks of data to be processed by the CryptoStream object. However, if an exception occurs before you call the Close method, the CryptoStream object might not be closed. To ensure that the Close method always gets called, place your call to the Close method within the finally block of a try/catch statement.

[满衣兄]

例子http://blog.csdn.net/nieyong/archive/2004/07/20/46453.aspx