/// <summary>
///
/// </summary>
/// <param name="owner"></param>
/// <param name="externalRow"></param>
private void ImportIntoOwner(DataRow externalRow, DataItemCollection owner)
{
// If we have an owner and we're exporting an external row, set our row as a new row of the owner's table
if (owner != null)
{
_owner = owner;
_row = _owner.InnerTable.NewRow();
}
// Set matching fields, check against the stand-alone item's fields
for (int i = 0; i < this.InnerTable.Columns.Count; i++)
{
// Get the name of the field
string fieldName = this.InnerTable.Columns[i].ColumnName;
// Get the index of the field for this item's row, can be different from the stand-alone version we're checking against
int currentRowIndex = _row.Table != this.InnerTable ? _row.Table.Columns.IndexOf(fieldName) : i;
// Get the index of the field in the external row
int externalRowIndex = externalRow.Table.Columns.IndexOf(fieldName);
if (currentRowIndex > -1 && externalRowIndex > -1)
{
// Apply the data to the collection row only if both the internal row and the external row have field
_row[currentRowIndex] = externalRow[externalRowIndex];
}
else if (externalRowIndex > -1)
{
// Apply the data to the retrieved field row since we already have it
if (_retrievedFieldRow == null)
{
// Create it if it's missing
_retrievedFieldRow = this.InnerTable.NewRow();
this.InnerTable.Rows.Add(_retrievedFieldRow);
}
_retrievedFieldRow[i] = externalRow[externalRowIndex];
}
else
{
// Otherwise mark it is as missing for RetrieveMissing to collect later on if necessary
_missingFields.Add(fieldName);
}
}
// This is a new addition June 3 2007
if (owner != null)
{
BackupFieldValues();
}
}
internal void SetParentCollection(DataItemCollection owner)
{
if (owner == null)
{
throw new ArgumentNullException("owner");
}
// Don't allow if item is already in collection-owned mode
if (_owner != null)
{
throw new InvalidOperationException("Cannot change the parent collection of an item that already belongs to a different collection.");
}
// Import our own row as an external row specifying an owner
ImportIntoOwner(this.Row, owner);
}
/// <summary>
/// Initializes an item with existing row data, either collection-based on independent mode.
/// </summary>
///
/// <param name="externalRow">
/// The row containing the item's data.
/// </param>
///
/// <param name="owner">
/// The collection that is creating the item. If null, the item is created as an independent item.
/// </param>
///
/// <param name="copyLocal">
/// If false, data is not copied into the internal table even if there is no owner specified.
/// </param>
///
/// <remarks>
/// <para>
/// If externalRow does not belong to the owner's InnerTable, the data will be imported into
/// the owner's table as a new row (or imported into the item's independent table if no owner is specified).
/// </para>
/// <para>
/// Fields that exist in the independent version of the item but do not exist in the external row will be
/// marked as "missing" so that if they are referenced in code their value will be retrieved on-demand.
/// </para>
/// </remarks>
protected internal DataItem(DataRow externalRow, DataItemCollection owner, bool copyLocal) : this()
{
// If no external row is specified, use a new empty row from the owner or the inner table
if (externalRow == null)
{
externalRow = owner != null?owner.InnerTable.NewRow() : InnerTable.NewRow();
}
// Collect missing column names
_missingFields = new ArrayList();
// Row data needs to be imported since we're not attaching to a collection
if (copyLocal && (owner == null || externalRow.Table != owner.InnerTable))
{
ImportIntoOwner(externalRow, owner);
}
else
{
_row = externalRow;
_owner = owner;
// Look for missing fields
foreach (DataColumn column in _table.Columns)
{
if (_row.Table.Columns.IndexOf(column.ColumnName) < 0)
{
_missingFields.Add(column.ColumnName);
}
}
}
if (!copyLocal || _owner != null)
{
// We don't need the table any more since we have an owner collection
_table.Dispose();
_table = null;
}
}
/// <summary>
///
/// </summary>
/// <param name="externalRow"></param>
/// <param name="owner"></param>
protected internal DataItem(DataRow externalRow, DataItemCollection owner) : this(externalRow, owner, true)
{
}