public DbContext(string connectionName = "Default", string databaseName = null)
{
DbContextData data = GetDbContextData(connectionName, databaseName);
SqlGenerator = new SqlGenerator(data.DbProvider);
DbConnection = data.DbProviderFactory.CreateConnection();
if (DbConnection == null)
{
throw new ArgumentNullException("connectionName");
}
DbConnection.ConnectionString = data.ConnectionString;
if (DbConnection.State != ConnectionState.Open)
{
DbConnection.Open();
}
}
private DbContextData CreateDbContextData(string connectionName = "Default", string databaseName = null)
{
DbContextData data = new DbContextData();
ConnectionName = connectionName;
ConnectionStringSettings setting = ConfigurationManager.ConnectionStrings[connectionName];
if (setting == null)
{
throw new Exception(string.Format("名为:{0}的节点不存在！", connectionName));
}
IDecryptProvider decryptProvider = null;
string strDecryptProvider = ConfigurationManager.AppSettings["Dapper.Extensions.DecryptProvider"];
if (!string.IsNullOrWhiteSpace(strDecryptProvider))
{
Type encryptProviderType = Type.GetType(strDecryptProvider, true);
decryptProvider = (IDecryptProvider)Activator.CreateInstance(encryptProviderType);
}
string connectionString = setting.ConnectionString;
if (decryptProvider != null)
{
connectionString = decryptProvider.Decrypt(setting.ConnectionString);
}
if (!string.IsNullOrWhiteSpace(databaseName))
{
connectionString = string.Format(connectionString, databaseName);
}
Type dbConnectionType = Type.GetType(setting.ProviderName, true);
IDbProvider dbProvider = (IDbProvider)Activator.CreateInstance(dbConnectionType);
DbProviderFactory dbProviderFactory = DbProviderFactories.GetFactory(dbProvider.ProviderName);
data.ConnectionString = connectionString;
data.DbProvider = dbProvider;
data.DbProviderFactory = dbProviderFactory;
return(data);
}