/// <summary>
/// 异步执行SQL 语句，并返回 <see cref="IEnumerable"/> 对象
/// </summary>
/// <typeparam name="T">实体类型</typeparam>
/// <param name="cmd">SQL 命令</param>
/// <param name="definition">命令定义对象，用于解析实体的外键</param>
/// <returns></returns>
async Task <List <T> > ExecuteListAsync <T>(IDbCommand cmd, SelectDbCommandDefinition definition)
{
IDataReader reader = null;
List <T> objList = new List <T>();
try
{
reader = await this.ExecuteReaderAsync(cmd);
TypeDeserializer deserializer = new TypeDeserializer(reader, definition);
objList = await deserializer.DeserializeAsync <T>();
}
finally
{
if (cmd != null)
{
cmd.Dispose();
}
if (reader != null)
{
reader.Dispose();
}
this.InternalDispose();
}
return(objList);
}
// 执行SQL 语句，并返回单个实体对象
async Task <T> ExecuteAsync <T>(IDbCommand cmd, SelectDbCommandDefinition definition)
{
IDataReader reader = null;
IDbConnection conn = null;
try
{
reader = await this.ExecuteReaderAsync(cmd);
conn = cmd != null ? cmd.Connection : null;
TypeDeserializer deserializer = new TypeDeserializer(reader, definition);
List <T> result = await deserializer.DeserializeAsync <T>();
return(result.FirstOrDefault());
}
finally
{
if (cmd != null)
{
cmd.Dispose();
}
if (reader != null)
{
reader.Dispose();
}
this.InternalDispose();
}
}
/// <summary>
/// 实例化<see cref="TypeDeserializer"/> 类的新实例
/// </summary>
/// <param name="reader">DataReader</param>
/// <param name="definition">SQL 命令描述</param>
internal TypeDeserializer(IDataReader reader, SelectDbCommandDefinition definition)
{
_reader = reader;
_definition = definition;
_deserializers = new Dictionary <string, Func <IDataRecord, object> >(8);
_listNavigationKeys = new Dictionary <string, HashSet <string> >(8);
}
// 执行SQL 语句，并返回单个实体对象
T Execute <T>(IDbCommand cmd, SelectDbCommandDefinition definition)
{
IDataReader reader = null;
try
{
reader = this.ExecuteReader(cmd);
TypeDeserializer deserializer = new TypeDeserializer(reader, definition);
List <T> result = deserializer.Deserialize <T>();
return(result.FirstOrDefault());
}
finally
{
if (cmd != null)
{
cmd.Dispose();
}
if (reader != null)
{
reader.Dispose();
}
this.InternalDispose();
}
}
/// <summary>
/// 实体化 <see cref="TypeDeserializer"/> 类的新实例
/// </summary>
/// <param name="reader">DataReader</param>
/// <param name="definition">命令描述对象，用于解析实体的外键</param>
public TypeDeserializer(IDataReader reader, SelectDbCommandDefinition definition)
{
_definition = definition;
_reader = reader;
}
