/// <summary>
/// 清除子对象集合
/// </summary>
/// <param name="oldEntity">The old entity.</param>
/// <param name="entityInfo">The entity information.</param>
protected virtual void MakeSavedCore(Entity oldEntity, EntityMeta entityInfo)
{
foreach (var item in entityInfo.ChildrenProperties)
{
var mp = item.ManagedProperty as IListProperty;
//如果是懒加载属性，并且没有加载数据时，不需要遍历此属性值
if (!oldEntity.FieldExists(mp)) continue;
var children = oldEntity.GetProperty(mp) as EntityList;
if (children == null) continue;
//清除已删除数据
children.CastTo<EntityList>().DeletedList.Clear();
//所有子对象，都标记为已保存
for (int i = children.Count - 1; i >= 0; i--)
{
var child = children[i] as Entity;
if (child.IsDirty || child.IsNew) MakeSaved(child);
}
}
oldEntity.MarkSaved();
}
/// <summary>
/// 删除不必要的对象，只留下需要保存的“脏”数据
/// </summary>
/// <param name="diffEntity">The difference entity.</param>
/// <param name="entityInfo">The entity information.</param>
protected virtual void ClearDataCore(Entity diffEntity, EntityMeta entityInfo)
{
foreach (var item in entityInfo.ChildrenProperties)
{
var mp = item.ManagedProperty;
//如果是懒加载属性，并且没有加载数据时，不需要遍历此属性值
if (!diffEntity.FieldExists(mp)) continue;
var children = diffEntity.GetProperty(mp) as EntityList;
if (children == null) continue;
for (int i = children.Count - 1; i >= 0; i--)
{
var child = children[i];
if (!child.IsDirty)
{
children.Remove(child);
children.DeletedList.Remove(child);
}
else
{
this.ClearData(child);
}
}
}
}
internal int Update(IDbAccesser dba, Entity item)
{
EnsureMappingTable();
var parameters = new List<object>(10);
string updateSql = null;
//是否有需要更新的 lob 字段。
bool hasUpdatedLOBColumns = false;
List<RdbColumn> lobColumns = null;
if (_hasLOB)
{
lobColumns = new List<RdbColumn>();
for (int i = 0, c = _columns.Count; i < c; i++)
{
var column = _columns[i];
//如果一个 lob 属性的值存在，则表示需要更新。
//（可能被设置了，也可能只是简单地读取了一下，没有变更值。这时也简单地处理。）
if (column.IsLOB && item.FieldExists(column.Info.Property))
{
lobColumns.Add(column);
hasUpdatedLOBColumns = true;
}
}
}
if (!hasUpdatedLOBColumns)
{
//如果没有 LOB，则直接缓存上更新语句。
if (_updateSQL == null) { _updateSQL = this.GenerateUpdateSQL(null); }
updateSql = _updateSQL;
}
else
{
updateSql = this.GenerateUpdateSQL(lobColumns);
}
//更新所有非 lob 的字段
for (int i = 0, c = _columns.Count; i < c; i++)
{
var column = _columns[i];
if (!column.Info.IsPrimaryKey && !column.IsLOB)
{
var value = column.ReadParameterValue(item);
parameters.Add(value);
}
}
//更新需要更新的 lob 字段
if (hasUpdatedLOBColumns)
{
for (int i = 0, c = lobColumns.Count; i < c; i++)
{
var column = lobColumns[i];
if (!column.Info.IsPrimaryKey)
{
var value = column.ReadParameterValue(item);
parameters.Add(value);
}
}
}
//Id 最后加入
parameters.Add(item.Id);
int res = dba.ExecuteText(updateSql, parameters.ToArray());
return res;
}
