+Returns wxCHK\_UNCHECKED when the checkbox is unchecked, wxCHK\_CHECKED
+ when it is checked and wxCHK\_UNDETERMINED when it's in the undetermined
+state. Asserts when the function is used with a 2-state checkbox.
+
+\membersection{wxCheckBox::Is3rdStateAllowedForUser}\label{wxcheckboxis3rdstateallowedforuser}
+
+\constfunc{bool}{Is3rdStateAllowedForUser}{\void}
+
+Returns whether or not the user can set the checkbox to the third state.
+
+\wxheading{Return value}
+
+Returns \true if the user can set the third state of this checkbox, \false if it can only be set
+programmatically or if it's a 2-state checkbox.
+
+\membersection{wxCheckBox::Is3State}\label{wxcheckboxis3state}
+
+\constfunc{bool}{Is3State}{\void}
+
+Returns whether or not the checkbox is a 3-state checkbox.
+
+\wxheading{Return value}
+
+Returns \true if this checkbox is a 3-state checkbox, \false if it's a 2-state checkbox.
+
+\membersection{wxCheckBox::IsChecked}\label{wxcheckboxischecked}
+
+\constfunc{bool}{IsChecked}{\void}
+
+This is just a maybe more readable synonym for
+\helpref{GetValue}{wxcheckboxgetvalue}: just as the latter, it returns
+\true if the checkbox is checked and \false otherwise.