How to write the simplest Windows program?
 

This is the program:
The Form has 3 TextBoxes and 1 Button. The user uses the keyboard to
enter a number in each of the two first TexBoxes, presses the Button,
and the sum of the numbers appears in the third TextBox.

In Borland Builder the OnClick event of the Button can look like this
(if the TextBoxes are named N1, N2 and N3):

void __fastcall TForm1::Button1Click(TObject *Sender)
{
double A = N1->Text.ToDouble();
double B = N2->Text.ToDouble();

N3->Text=A+B;
}

In MS Visual C++ 2005 Express Edition I miss the ToDouble function. How
can it be done here? Can anyone help ?

Regards Knut

Re: How to write the simplest Windows program?
 

Knut Olsen-Solberg wrote:
> This is the program:
> The Form has 3 TextBoxes and 1 Button. The user uses the keyboard to
> enter a number in each of the two first TexBoxes, presses the Button,
> and the sum of the numbers appears in the third TextBox.
>
> In Borland Builder the OnClick event of the Button can look like this
> (if the TextBoxes are named N1, N2 and N3):
>
> void __fastcall TForm1::Button1Click(TObject *Sender)
> {
> double A = N1->Text.ToDouble();
> double B = N2->Text.ToDouble();
>
> N3->Text=A+B;
> }
>
> In MS Visual C++ 2005 Express Edition I miss the ToDouble function. How
> can it be done here? Can anyone help ?
>
> Regards Knut

Take a look at std::strtod in <cstdlib>.

That should convert a string to a double. You'll have to pass it a
C-string though, but your text control surely has some conversion for this.

--John Ratliff

Re: How to write the simplest Windows program?
 

Knut Olsen-Solberg napisał(a):
> This is the program:
> The Form has 3 TextBoxes and 1 Button. The user uses the keyboard to
> enter a number in each of the two first TexBoxes, presses the Button,
> and the sum of the numbers appears in the third TextBox.
>
> In Borland Builder the OnClick event of the Button can look like this
> (if the TextBoxes are named N1, N2 and N3):
>
> void __fastcall TForm1::Button1Click(TObject *Sender)
> {
> double A = N1->Text.ToDouble();
> double B = N2->Text.ToDouble();
>
> N3->Text=A+B;
> }
>
> In MS Visual C++ 2005 Express Edition I miss the ToDouble function. How
> can it be done here? Can anyone help ?
>
> Regards Knut

double A = Double::Parse(Text);

Regards Ryszard

Re: How to write the simplest Windows program?
 

Ryszard wrote:
> Knut Olsen-Solberg napisał(a):
>> This is the program:
>> The Form has 3 TextBoxes and 1 Button. The user uses the keyboard to
>> enter a number in each of the two first TexBoxes, presses the Button,
>> and the sum of the numbers appears in the third TextBox.
>>
>> In Borland Builder the OnClick event of the Button can look like this
>> (if the TextBoxes are named N1, N2 and N3):
>>
>> void __fastcall TForm1::Button1Click(TObject *Sender)
>> {
>> double A = N1->Text.ToDouble();
>> double B = N2->Text.ToDouble();
>>
>> N3->Text=A+B;
>> }
>>
>> In MS Visual C++ 2005 Express Edition I miss the ToDouble function.
>> How can it be done here? Can anyone help ?
>>
>> Regards Knut
>
> double A = Double::Parse(Text);
>
> Regards Ryszard


Thanks!
Still I have a problem getting A+B back to N3->Text. Can you show me
this too?

Regards Knut

Re: How to write the simplest Windows program?
 

On Feb 20, 10:21 am, Knut Olsen-Solberg <k...@hist.no> wrote:
> Ryszard wrote:
> > Knut Olsen-Solberg napisał(a):
> >> This is the program:
> >> The Form has 3 TextBoxes and 1 Button. The user uses the keyboard to
> >> enter a number in each of the two first TexBoxes, presses the Button,
> >> and the sum of the numbers appears in the third TextBox.
>
> >> In Borland Builder the OnClick event of the Button can look like this
> >> (if the TextBoxes are named N1, N2 and N3):
>
> >> void __fastcall TForm1::Button1Click(TObject *Sender)
> >> {
> >> double A = N1->Text.ToDouble();
> >> double B = N2->Text.ToDouble();
>
> >> N3->Text=A+B;
> >> }
>
> >> In MS Visual C++ 2005 Express Edition I miss the ToDouble function.
> >> How can it be done here? Can anyone help ?
>
> >> Regards Knut
>
> > double A = Double::Parse(Text);
>
> > Regards Ryszard
>
> Thanks!
> Still I have a problem getting A+B back to N3->Text. Can you show me
> this too?

Might be a better way of doing this but this ought to work:

N3->Text = Convert::ToString(A + B, 10);

The 10 at the end means you want it in base 10, I hope this works for
non-integers too. By the way, this is kind of off-topic here, in the
future you should ask questions like these in a Microsoft/.Net-
specific newsgroup, perhaps microsoft.public.dotnet.languages.vc will
do.

--
Erik Wikström

Re: How to write the simplest Windows program?
 

Erik Wikström wrote:
> On Feb 20, 10:21 am, Knut Olsen-Solberg <k...@hist.no> wrote:
>> Ryszard wrote:
>>> Knut Olsen-Solberg napisał(a):
>>>> This is the program:
>>>> The Form has 3 TextBoxes and 1 Button. The user uses the keyboard to
>>>> enter a number in each of the two first TexBoxes, presses the Button,
>>>> and the sum of the numbers appears in the third TextBox.
>>>> In Borland Builder the OnClick event of the Button can look like this
>>>> (if the TextBoxes are named N1, N2 and N3):
>>>> void __fastcall TForm1::Button1Click(TObject *Sender)
>>>> {
>>>> double A = N1->Text.ToDouble();
>>>> double B = N2->Text.ToDouble();
>>>> N3->Text=A+B;
>>>> }
>>>> In MS Visual C++ 2005 Express Edition I miss the ToDouble function.
>>>> How can it be done here? Can anyone help ?
>>>> Regards Knut
>>> double A = Double::Parse(Text);
>>> Regards Ryszard
>> Thanks!
>> Still I have a problem getting A+B back to N3->Text. Can you show me
>> this too?
>
> Might be a better way of doing this but this ought to work:
>
> N3->Text = Convert::ToString(A + B, 10);
>
> The 10 at the end means you want it in base 10, I hope this works for
> non-integers too. By the way, this is kind of off-topic here, in the
> future you should ask questions like these in a Microsoft/.Net-
> specific newsgroup, perhaps microsoft.public.dotnet.languages.vc will
> do.
>
> --
> Erik Wikström

No, this did not work (maybe just a little correction needed?), but I
found something that worked:
T3->Text = (A+B).ToString();

Thanks Knut

Re: How to write the simplest Windows program?
 

Knut Olsen-Solberg napisa³(a):
> Ryszard wrote:
>> Knut Olsen-Solberg napisa³(a):
>>> This is the program:
>>> The Form has 3 TextBoxes and 1 Button. The user uses the keyboard to
>>> enter a number in each of the two first TexBoxes, presses the Button,
>>> and the sum of the numbers appears in the third TextBox.
>>>
>>> In Borland Builder the OnClick event of the Button can look like this
>>> (if the TextBoxes are named N1, N2 and N3):
>>>
>>> void __fastcall TForm1::Button1Click(TObject *Sender)
>>> {
>>> double A = N1->Text.ToDouble();
>>> double B = N2->Text.ToDouble();
>>>
>>> N3->Text=A+B;
>>> }
>>>
>>> In MS Visual C++ 2005 Express Edition I miss the ToDouble function.
>>> How can it be done here? Can anyone help ?
>>>
>>> Regards Knut
>>
>> double A = Double::Parse(Text);
>>
>> Regards Ryszard
>
>
> Thanks!
> Still I have a problem getting A+B back to N3->Text. Can you show me
> this too?
>
> Regards Knut

N3->Text = A.ToString();

Regards Ryszard