/// <summary>
/// 从POCO实体类获取跟当前实体类的属性名称相同的属性的值，拷贝到当前实体类中，完成数据的映射。
/// 要求拷贝的同名属性是读写属性且类型相同。
/// </summary>
/// <param name="pocoClass">POCO实体类，提供源数据</param>
/// <param name="isChange">是否改变属性的修改状态</param>
/// <returns>映射成功的属性数量</returns>
public int MapFrom(object pocoClass, bool isChange)
{
if (pocoClass == null)
{
return(0);
}
int count = 0;
int fcount = this.PropertyNames.Length;
INamedMemberAccessor[] accessors = new INamedMemberAccessor[fcount];
DelegatedReflectionMemberAccessor drm = new DelegatedReflectionMemberAccessor();
Type type = pocoClass.GetType();
var ef = EntityFieldsCache.Item(this.GetType());
for (int i = 0; i < fcount; i++)
{
//实体类的属性字段可能跟属性名称不一样 edit at 2015.2.11
string perpertyName = ef.GetPropertyName(PropertyNames[i]);
accessors[i] = drm.TryFindAccessor(type, perpertyName);
}
for (int i = 0; i < fcount; i++)
{
if (accessors[i] != null)
{
this.PropertyValues[i] = accessors[i].GetValue(pocoClass);
if (isChange) //设置属性修改状态
{
this.changedlist[i] = true;
}
count++;
}
}
return(count);
}
public List <T> QueryList <T>(IDataReader reader) where T : class, new()
{
List <T> list = new List <T>();
using (reader)
{
if (reader.Read())
{
int fcount = reader.FieldCount;
INamedMemberAccessor[] accessors = new INamedMemberAccessor[fcount];
DelegatedReflectionMemberAccessor drm = new DelegatedReflectionMemberAccessor();
for (int i = 0; i < fcount; i++)
{
accessors[i] = drm.FindAccessor <T>(reader.GetName(i));
}
do
{
T t = new T();
for (int i = 0; i < fcount; i++)
{
if (!reader.IsDBNull(i))
{
accessors[i].SetValue(t, reader.GetValue(i));
}
}
list.Add(t);
} while (reader.Read());
}
}
return(list);
}
/// <summary>
/// 将当前实体类的属性值映射到相同属性名称的POCO实体类中。要求拷贝的同名属性是读写属性且类型相同。
/// </summary>
/// <param name="pocoClass">POCO实体类</param>
/// <returns>映射成功的属性数量</returns>
public int MapToPOCO(object pocoClass)
{
if (pocoClass == null)
{
return(0);
}
int count = 0;
int fcount = this.PropertyNames.Length;
INamedMemberAccessor[] accessors = new INamedMemberAccessor[fcount];
DelegatedReflectionMemberAccessor drm = new DelegatedReflectionMemberAccessor();
Type type = pocoClass.GetType();
for (int i = 0; i < fcount; i++)
{
accessors[i] = drm.TryFindAccessor(type, PropertyNames[i]);
}
for (int i = 0; i < fcount; i++)
{
if (accessors[i] != null)
{
accessors[i].SetValue(pocoClass, this.PropertyValues[i]);
count++;
}
}
return(count);
}
/// <summary>
/// 采用快速的方法，将数据阅读器的结果映射到一个POCO类的列表上
/// </summary>
/// <typeparam name="T">POCO类类型</typeparam>
/// <param name="reader">抽象数据阅读器</param>
/// <returns>POCO类的列表</returns>
public static List <T> QueryList <T>(IDataReader reader) where T : class, new()
{
List <T> list = new List <T>();
using (reader)
{
if (reader.Read())
{
int fcount = reader.FieldCount;
//使用类型化委托读取正确的数据，解决MySQL等数据库可能的问题，感谢网友 @卖女孩的小肥羊 发现此问题
Dictionary <Type, MyFunc <IDataReader, int, object> > readerDelegates = DataReaderDelegate();
MyFunc <IDataReader, int, object>[] getDataMethods = new MyFunc <IDataReader, int, object> [fcount];
INamedMemberAccessor[] accessors = new INamedMemberAccessor[fcount];
DelegatedReflectionMemberAccessor accessorMethod = new DelegatedReflectionMemberAccessor();
for (int i = 0; i < fcount; i++)
{
accessors[i] = accessorMethod.FindAccessor <T>(reader.GetName(i));
//修改成从POCO实体类的属性上来获取DataReader类型化数据访问的方法，而不是之前的DataReader 的字段的类型
if (!readerDelegates.TryGetValue(accessors[i].MemberType, out getDataMethods[i]))
{
getDataMethods[i] = (rd, ii) => rd.GetValue(ii);
}
}
do
{
T t = new T();
for (int i = 0; i < fcount; i++)
{
if (!reader.IsDBNull(i))
{
MyFunc <IDataReader, int, object> read = getDataMethods[i];
object value = read(reader, i);
accessors[i].SetValue(t, value);
}
}
list.Add(t);
} while (reader.Read());
}
}
return(list);
}
/// <summary>
/// 从datareader读取数据到实体对象，实体的属性名称必须与数据库中的字段名称一致
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="reader"></param>
/// <returns></returns>
public static IEnumerable <T> ReadTo <T>(this IDataReader reader) where T : new()
{
List <T> list = new List <T>();
if (reader.Read())
{
int fcount = reader.FieldCount;
INamedMemberAccessor <T>[] accessors = new INamedMemberAccessor <T> [fcount];
PropertyAccessorManager drm = new PropertyAccessorManager();
for (int i = 0; i < fcount; i++)
{
accessors[i] = drm.FindAccessor <T>(reader.GetName(i));
}
do
{
T t = new T();
for (int i = 0; i < fcount; i++)
{
if (!reader.IsDBNull(i) && accessors[i] != null)
{
accessors[i].SetValue(t, reader.GetValue(i));
}
}
list.Add(t);
//yield return t;
} while (reader.Read());
}
if (reader != null)
{
reader.Close();
}
return(list);
}
/// <summary>
/// 将当前实体类的属性值（非空值）映射到相同属性名称的POCO实体类中。要求拷贝的同名属性是读写属性且类型相同。
/// </summary>
/// <param name="pocoClass">POCO实体类</param>
/// <returns>映射成功的属性数量</returns>
public int MapToPOCO(object pocoClass)
{
if (pocoClass == null)
{
return(0);
}
int count = 0;
int fcount = this.PropertyNames.Length;
INamedMemberAccessor[] accessors = new INamedMemberAccessor[fcount];
DelegatedReflectionMemberAccessor drm = new DelegatedReflectionMemberAccessor();
Type type = pocoClass.GetType();
var ef = EntityFieldsCache.Item(this.GetType());
for (int i = 0; i < fcount; i++)
{
//实体类的属性字段可能跟属性名称不一样 edit at 2015.10.24
string perpertyName = ef.GetPropertyName(PropertyNames[i]);
accessors[i] = drm.TryFindAccessor(type, perpertyName);
}
for (int i = 0; i < fcount; i++)
{
if (accessors[i] != null)
{
//this.PropertyValues[i] 可能为空，这会导致下面的赋值报错
//这种情况可能发生在实体类的数据是经过OQL部分Select 字段造成的，或者字段本身的值为NULL
object Value = this.PropertyValues[i];
if (Value != null && Value != DBNull.Value)
{
accessors[i].SetValue(pocoClass, this.PropertyValues[i]);
count++;
}
}
}
return(count);
}