old code:
for (int i = 0; i < gridTableInfo.Items.Count; i++)
{
try
{
DataGridRow neddrow = (DataGridRow)gridTableInfo.ItemContainerGenerator.ContainerFromIndex(i);
CheckBox cb = (CheckBox)gridTableInfo.Columns[0].GetCellContent(neddrow);
cb.IsChecked = ckbSelectedAll.IsChecked;
}
catch (Exception ex)
{
var nnn = ex;
}
}