INFO: CListBox::SelItemRange Selects Only Two or More Items (129428)

SUMMARY

The documentation for CListBox::SelItemRange says that it can be used to select one or more items in a CListBox. This is not correct. SelItemRange can only be used to select two or more items. This is because CListBox::SelItemRange uses the windows message LB_SELITEMRANGEEX which deselects the item if the first and last index of the range are equal.

MORE INFORMATION

Here are two possible ways to enable the ability to select one or more items:

Test for the condition when the first and last items are equal, and in that case, use CListBox::SetSel. -or-
Use the windows message LB_SELITEMRANGE. The following code fragment demonstrates how to use this message. The code works when CMyListBox is derived from CListBox.

Sample Code

int CMyListBox::MySelItemRange (BOOL bSelect,
                                int nFirstItem,
                                int nLastItem)
{
   ASSERT_VALID(this);
   return (int)SendMessage(LB_SELITEMRANGE,
                              bSelect,
                              MAKELPARAM(nFirstItem,nLastItem));
}

NOTE: This problem was fixed in Microsoft Visual C++, 32-bit Edition, version 4.0. The following is from the Visual C++ 4.0 Books On-Line entry for CListBox::SelItemRange:

Selects multiple consecutive items in a multiple-selection list box.

Use this member function only with multiple-selection list boxes. If you need to select only one item in a multiple-selection list box that is, if nFirstIem is equal to nLastItem call the SetSel member function instead.