private List <T> query <T>(Query query, RowReaderCallback <T> callback, bool firstOnly = false)
{
List <T> result = new List <T>();
using (var sql = connect()) {
using (var cmd = new SqlCommand(useDatabase(query.build()), sql)) {
foreach (var a in query.arguments)
{
if (a.Value != null)
{
cmd.Parameters.AddWithValue(a.Key, a.Value);
}
}
sql.Open();
using (var dr = cmd.ExecuteReader()) {
var reader = new RowReader(dr);
while (dr.Read())
{
result.Add(callback(reader));
if (firstOnly)
{
break;
}
}
}
}
}
return(result);
}
/// <summary>
/// Returns the first matched row according to provided query,
/// invoking the callback, which is required to return the desired object.
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="query"></param>
/// <param name="callback"></param>
/// <returns></returns>
public T getFirst <T>(Query query, RowReaderCallback <T> callback)
{
var r = query <T>(query, callback, true);
if (r.Count == 0)
{
return(default(T));
}
else
{
return(r[0]);
}
}
/// <summary>
/// Returns all matched rows according to provided query,
/// invoking the callback each row, which is required to return the desired object.
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="query"></param>
/// <param name="callback"></param>
/// <returns></returns>
public List <T> query <T>(Query query, RowReaderCallback <T> callback)
{
return(query <T>(query, callback, false));
}
/// <summary>
/// Returns the first matched row according to provided query,
/// invoking the callback, which is required to return the desired object.
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="query"></param>
/// <param name="callback"></param>
/// <returns></returns>
public Model getFirst(Query query, RowReaderCallback <Model> callback)
{
return(getFirst <Model>(query, callback));
}
