public static string ResolveFromFile(string fileName)
{
ConnectionStringReference cnRef = null;
using (StreamReader reader = File.OpenText(fileName))
{
XmlSerializer xs = new XmlSerializer(typeof(ConnectionStringReference));
cnRef = (ConnectionStringReference)xs.Deserialize(reader);
}
if (!File.Exists(cnRef.Filename))
{
return(null);
}
XmlDocument doc = new XmlDocument();
doc.Load(cnRef.Filename);
string result = doc.SelectSingleNode(cnRef.XPath).InnerText;
if (cnRef.Encryption.HasValue)
{
result = DecryptString(result, cnRef.Encryption.Value);
}
return(result);
}
/// <summary>
/// Creates a ConnectionStringReference for a given connection string with optional encryption.
/// </summary>
/// <param name="name">Name of XML file (without path) that will be created in ~/App Data/Local/Connection String Ref</param>
/// <param name="connectionString">Connection string to reference, will be stored in ~/My Documents/Connection Strings/{Name}.xml</param>
/// <param name="encryption">Data protection scope of connection string</param>
public static string Create(string name, string connectionString, DataProtectionScope?encryption = null)
{
string refFile = GetFilename(name);
if (File.Exists(refFile))
{
throw new Exception($"Can't overwrite existing Connection String Reference file {refFile}");
}
string settingsFile = Path.Combine(
Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments),
"Connection Strings", name + ".xml");
string folder = Path.GetDirectoryName(settingsFile);
if (!Directory.Exists(folder))
{
Directory.CreateDirectory(folder);
}
var cnSettings = new ConnectionStringSettingsFile()
{
ConnectionString = (encryption.HasValue) ? EncryptString(connectionString, encryption.Value) : connectionString,
};
using (StreamWriter writer = File.CreateText(settingsFile))
{
XmlSerializer xs = new XmlSerializer(typeof(ConnectionStringSettingsFile));
xs.Serialize(writer, cnSettings);
}
ConnectionStringReference cnRef = new ConnectionStringReference()
{
Name = name,
Filename = settingsFile,
XPath = "/Settings/ConnectionString"
};
if (encryption.HasValue)
{
cnRef.Encryption = encryption.Value;
}
cnRef.Save();
return(settingsFile);
}