(untagged)

CInputBox 1.0

Nishant Sivakumar

0.00/5 (No votes)

30 Nov 2001

A CFrameWnd derived class that provides functionality similar to the VB InputBox function. You don't need a dialog resource to use the class!

Download source - 2 Kb

What the class does for you?

I've seen people often asking whether there is something in C++ like the InputBox function in Visual Basic. I guess the easy way is to create your own dialog class. But I thought an easier way would be to write a class that is not dependent on a resource. CInputBox can be used without having to create a dialog resource. It allows you to set the title of the input-box, the prompt and also the default text.

There are just two public functions in addition to the constructor, of course. The constructor needs to be passed a CWnd*. Mostly you can pass this as that parameter.

The main member function is ShowInputBox which is declared as follows:

int ShowInputBox(CString,CString,CString);

The first CString is the prompt to show. The second CString is the title text for the input-box and the third CString is the default text. All three may be null strings. Though I don't see that happening often for the first two parameters.

Always, always call CloseBox after you have shown the input-box. You can only show the box once. If you want to show it again you MUST call CloseBox and then start all over again from object-construction.

How to use the class?

First create your CInputBox object

CInputBox *m_inputbox = new CInputBox(this);

Now call the ShowInputBox function passing the prompt text, the title text and the default text
```
int rv = m_inputbox->ShowInputBox("Enter your age","Age box","");
```

Find out whether they cancelled the box or whether they clicked OK
```
if(rv==IDCANCEL)
    MessageBox("","You cancelled");
```

If they clicked OK you can retrieve the entered text using the InputText public member variable
```
if(rv==IDOK)
    MessageBox(m_inputbox->InputText,"the text you entered");
```

Now call CloseBox to avoid memory leaks
```
m_inputbox->CloseBox();
```

Some points that you should keep in mind

You can only call ShowInputBox once per object-life-time. Means you simply do it in three steps. Create the object, show the box, close the object. If you need to show an input-box more than once, then for each time you need to follow all three steps.
For some strange and as of now unknown reason, on one occasion, my sample program that used this class didn't terminate and was left hanging in memory. I haven't traced the problem yet. But please do let me know if you face a similar problem

Conclusion

This is just version 1. I guess it needs a lot of enhancements like the ability to call ShowInputBox repeatedly and the ability to specify the size and location of the window. I'll do that when I have time.

License

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