Find distinct values from a datatable / dataset

To filter the datatable based on the distinct value of a column, use the below code
dataSet.Tables(0).DefaultView.ToTable(true,"ColumnName") ;
or  dataTable.DefaultView.ToTable(true,"ColumnName") ;
where ColumnName is the name of the column whose distinct value is to be found.

Accept Button in WPF

How do we achieve the accept button and cancel button in WPF?
We just have to set the button attributes for enable those features.
      Accept Button - Button.IsDefault = "True"
      Cancel Button -  Button.IsCancel = "True"