/// <summary>
/// 将数据从查询结果容器中映射到实体中
/// </summary>
/// <typeparam name="T"></typeparam>
/// <returns></returns>
public IEnumerable <T> Map <T>() where T : EntityBase, new()
{
#region 旧方法代码，注释
/*
* if (this.Values == null)
* {
* int rowsCount = this.Execute();
* if (rowsCount <= 0)
* yield break;
*
* }
* if (this.Values != null && this.fieldNames != null)
* {
* if (this.Values.Count == 0)
* yield break;
*
* Dictionary<string, int> dictNameIndex = new Dictionary<string, int>();
* T entity = new T();
* string tabeName = entity.TableName;
* //查找字段匹配情况
* //entity.PropertyNames 存储的仅仅是查询出来的列名称，由于有连表查询，
* //如果要映射到指定的实体，还得检查当前列对应的表名称
* if (this.OQL.sql_fields.Contains("[" + tabeName + "]"))
* {
* //是连表查询
* for (int i = 0; i < this.fieldNames.Length; i++)
* {
* for (int j = 0; j < entity.PropertyNames.Length; j++)
* {
* string cmpString = "[" + tabeName + "].[" + entity.PropertyNames[j] + "]";
* if (this.OQL.sql_fields.Contains(cmpString))
* {
* dictNameIndex[this.fieldNames[i]] = i;
* break;
* }
* }
*
*
* }
* }
* else
* {
* for (int i = 0; i < this.fieldNames.Length; i++)
* {
* for (int j = 0; j < entity.PropertyNames.Length; j++)
* {
* if (this.fieldNames[i] == entity.PropertyNames[j])
* {
* dictNameIndex[this.fieldNames[i]] = i;
* break;
* }
* }
* }
* }
*
* //没有匹配的，提前结束
* if (dictNameIndex.Count == 0)
* yield break;
*
* int length = entity.PropertyValues.Length;
* foreach (object[] itemValues in this.Values)
* {
* for (int m = 0; m < length; m++)
* {
* //将容器的值赋值给实体的值元素
* string key = entity.PropertyNames[m];
* if (dictNameIndex.ContainsKey(key))
* entity.PropertyValues[m] = itemValues[dictNameIndex[key]];
* }
* yield return entity;
* //创建一个新实例
* entity = new T ();
* }
* }
* else
* {
* throw new Exception("EntityContainer 错误，执行查询没有返回任何行。");
* }
*/
#endregion
if (this.Values == null)
{
//可能执行本方法之前，并没有调用过 OQL的Select方法指定要查询的实体类属性，需要模拟调用一次。
if (this.OQL.selectedFieldInfo.Count == 0)
{
int fieldCount = 0;
foreach (EntityBase entity in this.OQL.GetAllUsedEntity())
{
for (int i = 0; i < entity.PropertyNames.Length; i++)
{
object value = entity[i];//模拟调用
fieldCount++;
}
}
this.OQL.Select(new object[fieldCount]);
}
int rowsCount = this.Execute();
if (rowsCount <= 0)
{
yield break;
}
}
if (this.Values != null && this.fieldNames != null)
{
if (this.Values.Count == 0)
{
yield break;
}
TableNameField[] fieldInfo = new TableNameField[this.OQL.selectedFieldInfo.Count];
//查找字段匹配情况
//entity.PropertyNames 存储的仅仅是查询出来的列名称
for (int i = 0; i < this.OQL.selectedFieldInfo.Count; i++)
{
TableNameField tnf = this.OQL.selectedFieldInfo[i];
tnf.Index = tnf.Entity.GetPropertyFieldNameIndex(tnf.Field);
fieldInfo[i] = tnf;
}
foreach (object[] itemValues in this.Values)
{
EntityBase itemEntity = null;
Type entityType = typeof(T);
for (int m = 0; m < fieldInfo.Length; m++)
{
//将容器的值赋值给实体的值元素
EntityBase entity = fieldInfo[m].Entity;
if (entity.GetType() == entityType)
{
itemEntity = entity;
int index = fieldInfo[m].Index;
entity.PropertyValues[index] = itemValues[m];
}
}
if (itemEntity == null)
{
throw new Exception("EntityContainer 错误，查询没有包含当前指定的实体类类型，请检查OQL语句。");
}
T resultEntity = (T)itemEntity.Clone();
yield return(resultEntity);
}
}
else
{
throw new Exception("EntityContainer 错误，执行查询没有返回任何行。");
}
}
/// <summary>
/// 二进制序列化
/// </summary>
/// <param name="entity">实体类实例</param>
/// <returns>字节数组</returns>
public static byte[] BinarySerialize(EntityBase entity)
{
MemoryStream ms = new MemoryStream();
BinaryWriter bw = new BinaryWriter(ms);
Type factEntityType = entity.GetType();
EntityFields ef = EntityFieldsCache.Item(factEntityType);
byte b;
//写入实体类标记
bw.Write(ENTITY_ITEM_FLAG);
int length = entity.PropertyValues.Length - 1;
for (int i = 0; i <= length; i++)
{
object obj = entity.PropertyValues[i];
//if (obj == System.DBNull.Value) obj = null;//DBNull.Value在Convert 的时候会失败
//为每个属性添加null标记
if (obj == System.DBNull.Value || obj == null)
{
b = 0;//ＮＵＬＬ标记
}
else
{
if (length == i)
{
b = byte.MaxValue;
}
else
{
b = 1; //如果标志位为 byte.MaxValue ，则表示已经写入所有的属性字段，可用于以后添加实体属性但又要成功读取原有的记录
}
}
bw.Write(b); //写入标记
if (b > 0)
{
Type propertyType = ef.GetPropertyType(entity.PropertyNames[i]);
if (propertyType == null)
{
throw new Exception("PDF.NET实体类序列化错误：未知的实体属性类型，请检查实体类的属性和字段定义是否匹配。");
}
switch (propertyType.Name)
{
case "Int32":
bw.Write(Convert.ToInt32(obj)); break;
case "String":
bw.Write(Convert.ToString(obj));
break;
case "DateTime":
bw.Write(Convert.ToDateTime(obj).ToBinary());
break;
case "Int16": bw.Write(Convert.ToInt16(obj)); break;
case "Int64": bw.Write(Convert.ToInt64(obj)); break;
case "Single": bw.Write(Convert.ToSingle(obj)); break;
case "Double": bw.Write(Convert.ToDouble(obj)); break;
case "Decimal": bw.Write(Convert.ToDecimal(obj)); break;
case "Boolean": bw.Write(Convert.ToBoolean(obj)); break;
case "Byte": bw.Write(Convert.ToByte(obj)); break;
case "Char": bw.Write(Convert.ToChar(obj)); break;
case "Byte[]":
Byte[] buffer = (Byte[])obj;
bw.Write(buffer.Length); //写入字节序列的长度
if (buffer.Length > 0)
{
bw.Write(buffer);
}
break;
}
}
}
bw.Close();
ms.Close();
return(ms.ToArray());
}
