/// <summary>
/// 执行SQL 语句，并返回 <see cref="IEnumerable"/> 对象
/// </summary>
/// <typeparam name="T">实体类型</typeparam>
/// <param name="query">SQL 命令</param>
/// <param name="transaction">事务</param>
/// <returns></returns>
public List <T> ExecuteList <T>(IDbQueryable <T> query, IDbTransaction transaction = null)
{
CommandDefine define = this.Parse(query);
IDbCommand cmd = this.CreateCommand(define.CommandText, transaction, define.CommandType, define.Parameters);
return(this.ExecuteList <T>(cmd, define));
}
/// <summary>
/// 执行SQL 语句，并返回单个实体对象
/// </summary>
/// <param name="cmd">SQL 命令</param>
/// <param name="define">命令定义对象，用于解析实体的外键</param>
/// <returns></returns>
public T Execute <T>(IDbCommand cmd, CommandDefine define = null)
{
IDataReader reader = null;
T TResult = default(T);
IDbConnection conn = null;
try
{
reader = this.ExecuteReader(cmd);
conn = cmd != null ? cmd.Connection : null;
TypeDeserializer <T> deserializer = new TypeDeserializer <T>(reader, define as CommandDefine_Select);
if (reader.Read())
{
TResult = deserializer.Deserialize();
}
return(TResult);
}
finally
{
Dispose(cmd, reader, conn);
}
}
/// <summary>
/// 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="define">命令定义对象，用于解析实体的外键</param>
/// <returns></returns>
public List <T> ExecuteList <T>(IDbCommand cmd, CommandDefine define = null)
{
IDataReader reader = null;
IDbConnection conn = null;
List <T> objList = new List <T>();
try
{
reader = this.ExecuteReader(cmd);
conn = cmd != null ? cmd.Connection : null;
TypeDeserializer <T> deserializer = new TypeDeserializer <T>(reader, define as CommandDefine_Select);
while (reader.Read())
{
objList.Add(deserializer.Deserialize());
}
//yield return reader.ToEntity<T>();
}
finally
{
Dispose(cmd, reader, conn);
}
return(objList);
}
/// <summary>
/// 将 <see cref="IDataRecord"/> 映射为实体
/// </summary>
/// <typeparam reader="T">数据源</typeparam>
/// <param name="reader">数据源</param>
/// <param name="define">命令定义</param>
/// <returns></returns>
public static T ToModel <T>(this IDataRecord reader, CommandDefine define = null)
{
object obj = null;
object[] values = null;
int index = 0;
// 基元类初始化 ########################
if (Reflection.TypeUtils.IsPrimitive(typeof(T)))
{
//if(reader.IsDBNull(0)) return default(T)
//obj = reader.GetValue(0);
//return obj is DBNull ? default(T) : (T)obj;
return(reader.IsDBNull(0) ? default(T) : (T)reader.GetValue(0));
}
// 匿名类初始化 ########################
TypeRuntimeInfo runtime = TypeRuntimeInfoCache.GetRuntimeInfo <T>();
Inte.XFramework.Reflection.Emit.ConstructorInvoker ctor = runtime.ConstructInvoker;
if (runtime.IsAnonymousType)
{
values = new object[reader.FieldCount];
reader.GetValues(values);
for (index = 0; index < values.Length; ++index)
{
if (values[index] is DBNull)
{
values[index] = null;
}
}
return((T)ctor.Invoke(values));
}
// 实体类初始化 ########################
T model = (T)ctor.Invoke();
values = new object[reader.FieldCount];
reader.GetValues(values);
// 计算导航属性所占用的索引，这些索引对应的值不会赋给 T 实体
var sc = define as CommandDefine_Select;
if (sc == null || (sc.NavDescriptors != null && sc.NavDescriptors.Count == 0))
{
// 直接跑SQL,则不解析导航属性
for (int i = 0; i < reader.FieldCount; ++i)
{
obj = values[i];
if (obj == DBNull.Value)
{
continue;
}
string name = reader.GetName(i);
var wrapper = runtime.GetWrapper(name) as MemberAccessWrapper;
if (wrapper != null)
{
SetProperty(model, wrapper, obj);
}
}
}
else
{
// 使用表达式查询，解析导航属性
bool nav = sc.NavDescriptors.Any(x => x.Value.Count > 0);
int min = nav ? sc.NavDescriptors.Min(x => x.Value.Start) : 0;
// 第一层
index = -1;
foreach (var kvp in sc.Columns)
{
index += 1;
obj = values[index];
if (obj == DBNull.Value)
{
continue;
}
if (nav && index >= min)
{
break;
}
var wrapper = runtime.GetWrapper(kvp.Value.Name) as MemberAccessWrapper;
if (wrapper != null)
{
SetProperty(model, wrapper, obj);
}
}
// 递归导航属性
if (runtime.NavWrappers.Count > 0)
{
ToModel_Navigation(model, values, sc, string.Empty);
}
}
return(model);
}
