Sorting The List Control

The ctList control can be sorted on any column. This can be done through two different methods. 

1. Mark a column as sortable (this is done at design time when creating the column headers) and then to click on the column header for the column that you want sorted. 
2. Use the SortList method. When a visible column is sorted, the sort will be based upon the character data within the column item.

However, there may be times when sorting based on character data is not sufficient (i.e. sorting on numeric values or dates). There is a method provided by the control that allows the control to be sorted on numeric data.

Sorting Non Character Data

By default, the data is sorted based on character data. However, this may not be sufficient when we need to sort integers, reals (like currency), and dates. In this case, we can set the ColumnDataType property to match the type of data that needs to be sorted. The control will automatically sort the control in the appropriate manner.

The list can also be sorted based on the data in the ListData and ListCargo properties. For instance, the example below will sort the data based on the ListData property whenever column 2 is sorted.

Note : While it is not possible to hide columns in ctList, you can assign text to columns that do not exist and sort the list based on that data. For instance, you can define 3 columns but supply text for each list item for four columns. If we sort the list based on the forth column, we essentially sort the data based on a hidden column.

Sorting Multiple Columns

It is possible to sort up to three columns at a time. The SortMultiColumns method allows the programmer to specify up to three different columns to be sorted. The method can be used both inside and outside the PreSort method. For instance…