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.
void AFXAPI DDX_LBString( CDataExchange* pDX, int nIDC, CString& value );
- 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.
Note 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.