The DDX_LBString function manages the transfer of CString data between a list box control in a dialog box, form view, or control view object and a CString data member of the dialog box, form view, or control view object.
A pointer to a CDataExchange object. The framework supplies this object to establish the context of the data exchange, including its direction.
The resource ID of the list box control associated with the control property.
A reference to a member variable of the dialog box, form view, or control view object with which data is exchanged.
When DDX_LBString is called to transfer data to a list box control, the first item in the control whose beginning matches value is selected. (To match the entire item rather than just a prefix, use DDX_LBStringExact.) If there are no matches, no items are selected. The matching is case-insensitive.
When DDX_LBString is called to transfer data from a list box control, value is set to the current list box selection. If no item is selected, value is set to a string of zero length.
If the list box is a drop-down list box, the value exchanged is limited to 255 characters.
For more information about DDX, see Dialog Data Exchange and Validation.