| private GetDependency ( ) : System.Data.DataColumn[] | ||
| return | System.Data.DataColumn[] | |
// Initialize candidate columns to new columnInfo and leave all non candidate columns to null
private void InitCandidateColumns()
{
_nCandidates = 0;
_candidateColumns = new ColumnInfo[_table.Columns.Count];
if (_rowFilter == null)
{
return;
}
DataColumn[] depColumns = _rowFilter.GetDependency();
for (int i = 0; i < depColumns.Length; i++)
{
if (depColumns[i].Table == _table)
{
_candidateColumns[depColumns[i].Ordinal] = new ColumnInfo();
_nCandidates++;
}
}
}
internal void HandleDependentColumnList(DataExpression oldExpression, DataExpression newExpression)
{
DataColumn[] dependency;
// remove this column from the dependentColumn list of the columns this column depends on.
if (oldExpression != null)
{
dependency = oldExpression.GetDependency();
foreach (DataColumn col in dependency)
{
Debug.Assert(null != col, "null datacolumn in expression dependencies");
col.RemoveDependentColumn(this);
if (col._table != _table)
{
_table.RemoveDependentColumn(this);
}
}
_table.RemoveDependentColumn(this);
}
if (newExpression != null)
{
// get the list of columns that this expression depends on
dependency = newExpression.GetDependency();
// add this column to dependent column list of each column this column depends on
foreach (DataColumn col in dependency)
{
col.AddDependentColumn(this);
if (col._table != _table)
{
_table.AddDependentColumn(this);
}
}
_table.AddDependentColumn(this);
}
}
