Get text from CComboBox

3
votes

I have a CDialog (myDialogBox) that has a CComboBox member (myComboBox). My goal is to get the user-typed text (preferably as a CString) from the edit portion of a dropdown style CComboBox. But, I cannot seem to get it to work.

I've tried using myComboBox.GetWindowText(myString). But whenever I run it in debug mode, my code breaks at ASSERT(::IsWindow(m_hWnd)) within the CWnd::GetWindowText() function.

I've also tried myDialogBox.GetDlgItemText(MY_COMBOBOX_ID, myString), which breaks down in a similar way.

Additionally, I've tried:

    COMBOBOXINFO info;
    memset(&info,0,sizeof(info));
    myComboBox.GetComboBoxInfo(&info);
    LPTSTR str = new TCHAR[::GetWindowTextLength(info.hwndItem)];
    ::GetWindowText(info.hwndItem,str,::GetWindowTextLength(info.hwndItem));

But, it doesn't seem to be populating my info variable correctly.

Could someone point me in the right direction, please? What am I doing wrong? Any suggestions?

EDIT: Just in case it might help understand my ultimate goal, I am trying to have a combo-box where that can help a user pic and choose from a listing of strings. Nonetheless, if he/she does not want any on the dropdown-list, he can come up with his own string. I'd like a way to receive his user-typed string.

2
visual-c++mfcccombobox
You should have an auto-generated DDX_Control line in your dialog's DoDataExchange() method mapping MY_COMBOBOX_ID to myComboBox. Also MY_COMBOBOX_ID should have a unique numerical value in resource.h. Without those you'd get behaviour such as you're describing. – acraig5075
Refering to my second response to Mark Ransom below... I believe I have those requirements. (including the value in resource.h) – JHowzer

2 Answers

6
votes

You need to call GetWindowText before the dialog is destroyed. A good place to do that would be in the DoDataExchange member function of the dialog.

Edit: You can also get an error if the CComboBox object hasn't been attached to the actual window. This also typically occurs in DoDataExchange.

2
votes

You can get the combo box text inline with the following code:

CString cStr;
CWnd* Pfield = GetDlgItem(MY_COMBOBOX_ID);
Pfield->GetWindowText(cStr);