internal ChildRowCollection(Row parentRow, ChildRelation relation, Table childTable, IEnumerable <Row> childRows)
: base(childRows.ToList())
{
ParentRow = parentRow;
ChildTable = childTable;
Relation = relation;
}
//Returns an internal ChildRowCollection with AddRow
//and RemoveRow methods to allow ForeignKeyColumn to
//update the collection when it changes.
internal ChildRowCollection ChildRows(ChildRelation relation, bool forceCreate)
{
if (relation == null)
{
throw new ArgumentNullException("relation");
}
if (Table == null)
{
throw new InvalidOperationException("Child relations cannot be used on detached rows");
}
if (Table.Context == null)
{
throw new InvalidOperationException("Child relations can only be used for tables inside a DataContext");
}
ChildRowCollection retVal;
if (!childRelations.TryGetValue(relation, out retVal) &&
forceCreate)
{
var childTable = Table.Context.Tables[relation.ChildSchema];
if (childTable == null)
{
throw new InvalidOperationException("Cannot find " + relation.ChildSchema.Name + " table");
}
retVal = new ChildRowCollection(
this, relation, childTable,
relation.ChildColumn.HasIndex
? childTable.GetIndex(relation.ChildColumn).GetOrNull(this) ?? Enumerable.Empty <Row>()
: childTable.Rows.Where(r => r[relation.ChildColumn] == this));
childRelations.Add(relation, retVal);
}
return(retVal);
}
///<summary>Gets the child rows in the specified child relation.</summary>
///<returns>A ChildRowCollection containing a live view of the child rows.</returns>
public IChildRowCollection <Row> ChildRows(ChildRelation relation)
{
return(ChildRows(relation, true));
}
internal void OnRelationRemoved(ChildRelation relation)
{
childRelations.Remove(relation); typedChildRelations.Remove(relation);
} //Won't throw if not found