/// <summary>
/// 根据ID载入实体
/// </summary>
/// <param name="id">实体对象的Id</param>
/// <param name="fetchType">加载对象的方式,例如是否加载引用对象和集合属性</param>
public void Load(long id, Fetch fetchType)
{
this.Id = id;
string sqlPattern = string.Empty;
string sql = string.Empty;
StringBuilder sbSelectStr = new StringBuilder();
string strLeftJoin = string.Empty;
DataSet ds = null;
sbSelectStr.Append(string.Format("{0}.id as E_{0}Id,{0}.*", EInfo.EntityName));
sqlPattern = "select {0} from {1} {2} where {1}.id={3}";
strLeftJoin = DBSQLiteHelper.GenerateLeftJoinSQL(EInfo.References, ref sbSelectStr, fetchType);
strLeftJoin += DBSQLiteHelper.GenerateSetSQL(EInfo.Sets, ref sbSelectStr, fetchType);
if (EInfo.REFSelf)
{
strLeftJoin += DBSQLiteHelper.GenerateREFSelfSQL(EInfo, ref sbSelectStr, fetchType);
}
sql = string.Format(sqlPattern, sbSelectStr.ToString(), EInfo.EntityName, strLeftJoin, id);
ds = DBSQLiteHelper.ExecuteQuery(sql);
if (ds != null && ds.Tables.Count > 0 && ds.Tables[0].Rows.Count > 0)
{
foreach (FieldAttribute pinfo in EInfo.Properties)
{
DBSQLiteHelper.FetchPropertyValue(this, pinfo, ds.Tables[0], 0);
}
foreach (REFAttribute refAtt in EInfo.References)
{
if ((fetchType == Fetch.Default && !refAtt.LazyLoad) || fetchType == Fetch.REFS || fetchType == Fetch.REFSandSets)
{
DBSQLiteHelper.FetchREFEntity(this, refAtt, ds.Tables[0]);
}
}
foreach (SETAttribute setAtt in EInfo.Sets)
{
if ((fetchType == Fetch.Default && !setAtt.LazyLoad) || fetchType == Fetch.SETS || fetchType == Fetch.REFSandSets)
{
DBSQLiteHelper.FetchSet(this, setAtt, ds.Tables[0]);
}
}
//如果实体有对自身实体对象的引用
if (EInfo.REFSelf)
{
if (fetchType == Fetch.REFS)
{
DBSQLiteHelper.FetchParent(this, ds.Tables[0], 0);
}
else if (fetchType == Fetch.SETS)
{
DBSQLiteHelper.FetchChildren(this, ds.Tables[0]);
}
else if (fetchType == Fetch.REFSandSets)
{
DBSQLiteHelper.FetchParent(this, ds.Tables[0], 0);
DBSQLiteHelper.FetchChildren(this, ds.Tables[0]);
}
}
}
}
/// <summary>
/// 根据从数据库检索出的数据集从中组装出实体对象实例
/// </summary>
/// <param name="einfo">实体对象媒数据</param>
/// <param name="fetchType">关联对象加载方式</param>
/// <param name="table">数据集</param>
/// <param name="rowIndex">实体对象所处的数据集行数</param>
/// <returns>实体对象实例</returns>
public static BaseEntity FetchEntity(EntityInfo einfo, Fetch fetchType, DataTable table, int rowIndex)
{
BaseEntity entity = (BaseEntity)DLLAnalysis.GetEntityInstance(einfo.EntityName);
entity.Id = Convert.ToInt64(table.Rows[rowIndex][einfo.IdNameInSelect]);
foreach (FieldAttribute pinfo in einfo.Properties)
{
DBSQLiteHelper.FetchPropertyValue(entity, pinfo, table, rowIndex);
}
foreach (REFAttribute refAtt in einfo.References)
{
if ((fetchType == Fetch.Default && !refAtt.LazyLoad) || fetchType == Fetch.REFS || fetchType == Fetch.REFSandSets)
{
DBSQLiteHelper.FetchREFEntity(entity, refAtt, table);
}
}
foreach (SETAttribute setAtt in einfo.Sets)
{
if ((fetchType == Fetch.Default && !setAtt.LazyLoad) || fetchType == Fetch.SETS || fetchType == Fetch.REFSandSets)
{
DBSQLiteHelper.FetchSet(entity, setAtt, table);
}
}
//如果实体有对自身实体对象的引用
if (einfo.REFSelf)
{
if (fetchType == Fetch.REFS)
{
FetchParent(entity, table, rowIndex);
}
else if (fetchType == Fetch.SETS)
{
FetchChildren(entity, table);
}
else if (fetchType == Fetch.REFSandSets)
{
FetchParent(entity, table, rowIndex);
FetchChildren(entity, table);
}
}
return(entity);
}
