From Tracker Software PDF SDK
Changes state of an item in a dialog to checked or unchecked by item's text ID.
HRESULT CheckItem([in] BSTR sItemID, [in] LONG nNewCheckState, [in, defaultvalue(-1)] VARIANT_BOOL bUpdateRadioGroup);
- [in] Text ID of an item that is to be checked/unchecked.
- [in] Checks an item if set to TRUE, unchecks if set to FALSE.
- [in, defaultvalue(-1)] if set to VARIANT_TRUE, updates state of all radio boxes of the same group unchecking items that were in a checked state.
Returns S_OK if operation was successful or error code in other cases.