/// <summary>
/// 将从数据库中获取的数据行转化为指定的实体
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="dr">The dr.</param>
/// <returns></returns>
protected virtual T FillEntityFromDataReader(SqlDataReader dr)
{
var builder = DynamicBuilder <T> .CreateBuilder(dr);
var instance = builder.Build(dr);
return(instance);
}
/// <summary>
/// 将DataReader的属性值转化为实体类的属性值，返回实体类
/// (提供了默认的反射机制获取信息，为了提高性能，建议重写该函数)
/// </summary>
/// <param name="dr">有效的DataReader对象</param>
/// <returns>
/// 实体类对象
/// </returns>
protected virtual T DataReaderToEntity(IDataReader dr)
{
var obj = new T();
var builder = DynamicBuilder <T> .CreateBuilder(dr);
while (dr.Read())
{
obj = builder.Build(dr);
}
return(obj);
}
/// <summary>
/// 通用获取集合对象方法
/// </summary>
/// <param name="sql">查询的Sql语句</param>
/// <param name="commandType">Type of the command.</param>
/// <param name="paramList">参数列表，如果没有则为null</param>
/// <param name="connection">The connection.</param>
/// <param name="transaction">The transaction.</param>
/// <returns></returns>
public List <T> GetList(string sql, CommandType commandType, IDbDataParameter[] paramList, DbConnection connection, DbTransaction transaction)
{
DateTime start = DateTime.Now;
var list = new List <T>();
try
{
var dbc =
transaction == null
? new SqlCommand(sql, (SqlConnection)connection)
{
CommandType = commandType
}
: new SqlCommand(sql, (SqlConnection)connection, (SqlTransaction)transaction)
{
CommandType = commandType
};
if (paramList != null)
{
dbc.Parameters.AddRange(paramList);
}
using (IDataReader dr = dbc.ExecuteReader())
{
DynamicBuilder <T> builder = DynamicBuilder <T> .CreateBuilder(dr);
while (dr.Read())
{
T entity = builder.Build(dr);
if (!list.Contains(entity))
{
list.Add(entity);
}
}
}
dbc.Parameters.Clear();
}
catch (Exception ex)
{
Logger.Error(sql);
Logger.Error(ex);
}
Logger.Debug($"Execute {commandType} : {sql} cost {DateTime.Now.Subtract(start).TotalMilliseconds} ms.");
return(list);
}
/// <summary>
/// Fills the entity from reader.
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="dr">The dr.</param>
/// <returns></returns>
protected virtual List <T> FillEntitiesFromReader(SqlDataReader dr)
{
var list = new List <T>();
DynamicBuilder <T> builder = DynamicBuilder <T> .CreateBuilder(dr);
using (SqlDataReader reader = dr)
{
while (reader.Read())
{
var instance = builder.Build(reader);
if (!list.Contains(instance))
{
list.Add(instance);
}
}
}
return(list);
}
/// <summary>
/// Creates the builder.
/// </summary>
/// <param name="dataRecord">The data record.</param>
/// <returns></returns>
public static DynamicBuilder <T> CreateBuilder(IDataRecord dataRecord)
{
DynamicBuilder <T> dynamicBuilder = new DynamicBuilder <T>();
DynamicMethod method = new DynamicMethod("DynamicCreate", typeof(T), new Type[] { typeof(IDataRecord) }, typeof(T), true);
ILGenerator generator = method.GetILGenerator();
LocalBuilder result = generator.DeclareLocal(typeof(T));
generator.Emit(OpCodes.Newobj, typeof(T).GetConstructor(Type.EmptyTypes));
generator.Emit(OpCodes.Stloc, result);
for (int i = 0; i < dataRecord.FieldCount; i++)
{
PropertyInfo propertyInfo = typeof(T).GetProperty(dataRecord.GetName(i));
Label endIfLabel = generator.DefineLabel();
if (propertyInfo != null && propertyInfo.GetSetMethod() != null)
{
generator.Emit(OpCodes.Ldarg_0);
generator.Emit(OpCodes.Ldc_I4, i);
generator.Emit(OpCodes.Callvirt, isDBNullMethod);
generator.Emit(OpCodes.Brtrue, endIfLabel);
generator.Emit(OpCodes.Ldloc, result);
generator.Emit(OpCodes.Ldarg_0);
generator.Emit(OpCodes.Ldc_I4, i);
generator.Emit(OpCodes.Callvirt, getValueMethod);
generator.Emit(OpCodes.Unbox_Any, dataRecord.GetFieldType(i));
generator.Emit(OpCodes.Callvirt, propertyInfo.GetSetMethod());
generator.MarkLabel(endIfLabel);
}
}
generator.Emit(OpCodes.Ldloc, result);
generator.Emit(OpCodes.Ret);
dynamicBuilder.handler = (Load)method.CreateDelegate(typeof(Load));
return(dynamicBuilder);
}
