/// <summary>
/// 日志解密
/// </summary>
/// <param name="sourceFilePath">加密后的日志文件</param>
/// <param name="targetFilePath">解密后的日志文件</param>
/// <param name="key">//密钥(长度必须8位以上)</param>
public static void DecryptFile(string sourceFilePath, string targetFilePath, string key)
{
using (var streamReader = File.OpenText(sourceFilePath))
{
if (File.Exists(targetFilePath))
{
File.SetAttributes(targetFilePath, FileAttributes.Normal);
File.Delete(targetFilePath);
}
using (var streamWriter = File.CreateText(targetFilePath))
{
while (!streamReader.EndOfStream)
{
var line = streamReader.ReadLine();
string decryptString;
//将加密串首尾加上"VvvvV"以区分加密串和非加密串混合出现的情况
if ((line.StartsWith("VvvvV") && line.EndsWith("VvvvV")))
{
decryptString = DesEncryptHelper.DecryptString(line.Trim("VvvvV".ToCharArray()), key);
}
else
{
decryptString = line + "\r\n";
}
streamWriter.Write(decryptString);
}
streamWriter.Flush();
//streamWriter.Close();
}
}
}
private static string GetConnectionString(Operation operation, string connectionString, string key, string passwordPart, string separator)
{
if (string.IsNullOrEmpty(connectionString))
{
throw new ArgumentNullException("connectionString");
}
var passwordUnit = connectionString
.Split(separator.ToCharArray(), StringSplitOptions.RemoveEmptyEntries)
.FirstOrDefault(
t => t.ToUpper().StartsWith(passwordPart.ToUpper())
);
if (string.IsNullOrEmpty(passwordUnit))
{
return(connectionString);
}
var passwordParts = passwordUnit.Split(new[] { '=' }, StringSplitOptions.RemoveEmptyEntries);
if (passwordParts.Length < 2)
{
return(connectionString);
}
switch (operation)
{
case Operation.Decrypt:
passwordParts[1] = DesEncryptHelper.DecryptString(passwordParts[1], key);
break;
case Operation.Encrypt:
passwordParts[1] = DesEncryptHelper.EncryptString(passwordParts[1], key);
break;
}
return(connectionString.Replace(passwordUnit, string.Join("=", passwordParts)));
}
