SetDlgItemInt Doesn't take negative numbers.

[Gz64jE8b]

I'm using SetDlgItemInt to use recieved input from the user, do some calculations then return the answer but it doesnt work with negative numbers, this is a problem due to the fact that this particular program uses negative numbers 90% of the time.

How can I get it to recognise negative numbers?


Edit: Also I'm sometimes getting numbers like 1.34-e00, solution for that?

[Null]

Last parameter to GetDlgItemInt must be true,
GetDlgItemInt(hDlg,nIDDlgItem,lpTranslated,true);
see http://msdn.microsoft.com/en-us/library/ms645485(v=vs.85).aspx

[Gz64jE8b]

It's my SetDlgItemText that's the problem actually, when I use SetDlgItemInt I can work with negative numbers but not decimals, when I use SetDlgItemText I can use decimals but not negatives.

Is there a way to use decimals with SetDlgItemInt?

[Gz64jE8b]

Nobody? :(

[webJose]

You say SetDlgItemInt() can work with negatives but not decimals. Does decimals mean floating point? Because the INT part of the function's name pretty much says it works with integers only.

As for SetDlgItemText(), it can display any text. Just use the stringstream method to convert whatever number (positive, negative, integer, floating point, etc.) to a string and then pass this string to SetDlgItemText().

Google up "c++ number to string stringstream".

[Gz64jE8b]

I can't find anything of use (most of the stuff is beyond my understanding).

Could you just supply a code snippit for me to work with?

(I'm not in a programming class so don't worry about doing my homework).

[modoran]

Like this:

std::basic_stringstream<TCHAR> ss;
ss << number;
SetDlgItemText(hwnd, nIDDlgItem ,ss.str().c_str() );
......

[Gz64jE8b]

Nothing has worked so far ^_^

[DSLq5Di1]

..and what do you expect from us? there is nothing wrong with the suggestions given, more likely your implementation has a problem. The more information (code/output/expected output/errors/etc..) you provide, the better our feedback can be.

[Gz64jE8b]

#define ID_TEXTBOXA 1
#define ID_TEXTBOXB 2
#define ID_TEXTBOXC 3
#define ID_TEXTBOXD 4
#define ID_TEXTBOXE 6
#define ID_BUTTON 5
#define BUFFER 14

TCHAR tchBuffer[BUFFER];

LRESULT CALLBACK WindowProcedure (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    switch (message)                  
    {
        case WM_CREATE:{
             {
             CreateWindow(TEXT("EDIT"), TEXT("A"), WS_VISIBLE | WS_CHILD | WS_BORDER | ES_AUTOHSCROLL, 
             20, 10, 200, 20, hwnd, (HMENU) ID_TEXTBOXA, NULL, NULL);
             }
             {
             CreateWindow(TEXT("EDIT"), TEXT("B"), WS_VISIBLE | WS_CHILD | WS_BORDER | ES_AUTOHSCROLL, 
             20, 40, 200, 20, hwnd, (HMENU) ID_TEXTBOXB, NULL, NULL);
             }
             {
             CreateWindow(TEXT("EDIT"), TEXT("C"), WS_VISIBLE | WS_CHILD | WS_BORDER | ES_AUTOHSCROLL, 
             20, 70, 200, 20, hwnd, (HMENU) ID_TEXTBOXC, NULL, NULL);
             }
             {
             CreateWindow(TEXT("STATIC"), TEXT("X"), WS_VISIBLE | WS_CHILD | WS_BORDER | ES_AUTOHSCROLL, 
             10, 300, 200, 20, hwnd, (HMENU) ID_TEXTBOXD, NULL, NULL);
             }
             {
             CreateWindow(TEXT("STATIC"), TEXT("X"), WS_VISIBLE | WS_CHILD | WS_BORDER | ES_AUTOHSCROLL, 
             10, 250, 200, 20, hwnd, (HMENU) ID_TEXTBOXE, NULL, NULL);
             }
             
             
             
             {
             CreateWindow(TEXT("BUTTON"), TEXT("Solve"), WS_VISIBLE | WS_CHILD, 
             250, 300, 130, 20, hwnd, (HMENU) ID_BUTTON, NULL, NULL);
             
             }
             break;
             }
        case WM_COMMAND:{
             
             if(LOWORD(wParam) == ID_BUTTON){
             double a;
             double b;
             double c;
             double d;
             double f;
             double g;

             
        a = GetDlgItemInt(hwnd, ID_TEXTBOXA, NULL, TRUE);
                     if( a == 0)
             {
                 MessageBox(hwnd, "Cannot divide by zero", "Error", MB_OK | MB_ICONERROR);
                 break;
                 }
        b = GetDlgItemInt(hwnd, ID_TEXTBOXB, NULL, TRUE);
        c = GetDlgItemInt(hwnd, ID_TEXTBOXC, NULL, TRUE);
        d = sqrt(((b*b)-(4*a*c)));
        f = ((-b+d)/(2*a));
        g = ((-b-d)/(2*a));
        if (((b*b)-(4*a*c)) < 0 )
        {
        MessageBox(hwnd, "Cannot square root a negative number", "Error", MB_OK | MB_ICONERROR);
        break;
        }
        SetDlgItemText(hwnd, ID_TEXTBOXD, _gcvt((f), 13, tchBuffer));
        SetDlgItemText(hwnd, ID_TEXTBOXE, _gcvt((g), 13, tchBuffer));
        }

             
             break;
             }
        case WM_DESTROY:
            PostQuitMessage (0);       
            break;
        default:                      
            return DefWindowProc (hwnd, message, wParam, lParam);
    }

    return 0;
}

Knock yourselves out

[DSLq5Di1]

Using a stringstream as webJose mentioned,

#include <sstream>
#include <string> 

template <typename T>
inline std::basic_string<TCHAR> t_str(const T& val)
{
    std::basic_ostringstream<TCHAR> oss;
    oss << val;

    return oss.str();
}

SetDlgItemText(hwnd, ID_TEXTBOXD, t_str(f).c_str());


There is no TCHAR mapping for _gcvt as far as I can see..
http://msdn.microsoft.com/en-us/library/tsbaswba

So if you wish to use a C function instead, I'd suggest _sntprintf_s.
http://msdn.microsoft.com/en-us/library/f30dzcf6

[Gz64jE8b]

The stringstream didn't work, I tried it.

[Null]

Can you post the code where you try to use stringstream?

[Gz64jE8b]

Everything you'll ever need is in the code above.

[webJose]

LOL! The stubburn kind I see.

A tip: If you are in need of help, especially with a topic above your current skill, you don't say "it's up there, deduce yourself". Instead you promptly volunteer whatever piece of information you were asked.

The stringstream approach works 100% OK. What you need to do is learn how to use it. Null seems willing to point out the correct approach if you show him/her where you are attempting the stringstream method.

[Gz64jE8b]

I tried the stringstream but I get an error message that tells me it can't be converted to a certain format (I forgot which one...)

[Null]

Can you post the error message?