private void InitializeDbSets()
{
var dbSetType = typeof(DbSet <>);
var dbSetDescriptors = TypeDescriptor.GetProperties(this).Cast <PropertyDescriptor>()
.Where(p => p.PropertyType.IsConstructedGenericType && p.PropertyType.GetGenericTypeDefinition().Equals(dbSetType));
var entityTypes = dbSetDescriptors.Select(p => p.PropertyType.GenericTypeArguments[0]);
foreach (var descriptor in dbSetDescriptors)
{
Type entityType = descriptor.PropertyType.GenericTypeArguments[0];
Type entityDbSetType = dbSetType.MakeGenericType(entityType);
var options = new DbSetOptions(this.connection, entityType, primaryKey);
object dbSet = Activator.CreateInstance(entityDbSetType, BindingFlags.NonPublic | BindingFlags.Instance, null, new object[] { options, this.dataSet }, CultureInfo.InvariantCulture);
descriptor.SetValue(this, dbSet);
}
}
internal DbSet(DbSetOptions options, DataSet dataSet)
{
this.options = options ?? throw new ArgumentNullException(nameof(options));
this.adapter = new SqlDataAdapter();
this.dataSet = dataSet;
string tableName = this.options.Table;
this.adapter.SelectCommand = new SqlCommand($"SELECT * FROM {tableName} WHERE 1=2", this.options.SqlConnection);
this.dataTable = new DataTable();
this.adapter.Fill(dataTable);
this.dataTable.TableName = tableName;
this.dataSet.Tables.Add(this.dataTable);
var sqlCommandBuilder = new SqlCommandBuilder(this.adapter);
this.outIdParameter = new SqlParameter("@id", SqlDbType.Int);
this.outIdParameter.Direction = ParameterDirection.Output;
Provider = new SqlProvider <TEntity>(this);
Expression = Expression.Constant(this);
this.mapper = new RowMapper(this.options);
this.commandBuilder = new CommandBuilder(options);
}