Makes Me So Blur!!!

hi,guys.here is my question.i want to type a something inside my window but cannot.The problem is,the window pop up everytimes i compiler but when i pressed any keys in my keyboards.The window is closed up already.
here is my code: pls solve it for me.
where is the error and problem?
Solution:i want to enter something inside my window.

here is the code:
pls run this program before u make any modification.as it contain two error in it.Thanks.

#include<windows.h>

long FAR PASCAL WndProc(HWND ,UINT, WPARAM,LPARAM);

int PASCAL WinMain(HANDLE hInst,HANDLE hPrevInstance,LPSTR lpszCmdLine,int nCmdShow)
{
HWND hWnd;
MSG msg;
WNDCLASS wndclass;



if(!hPrevInstance)
{
wndclass.style=0;
wndclass.lpfnWndProc=(WNDPROC)WndProc;
wndclass.cbClsExtra=0;
wndclass.cbWndExtra=0;
wndclass.hInstance=hInst;
wndclass.hIcon=LoadIcon(hInst,IDI_APPLICATION);
wndclass.hCursor=LoadCursor(NULL,IDC_ARROW);
wndclass.hbrBackground=GetStockObject(WHITE_BRUSH) ;
wndclass.lpszMenuName=MAKEINTRESOURCE(NULL); wndclass.lpszClassName="MyClass";
if(!RegisterClass(&wndclass))
return 0;
}
hWnd=CreateWindow("MyClass","Student Pre-App Form",WS_OVERLAPPEDWINDOW,10,10,300,300,NULL,NULL, hInst,NULL);
ShowWindow(hWnd,nCmdShow);

while(GetMessage(&msg,0,0,0))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
return(msg.wParam);
}

long FAR PASCAL WndProc(HWND hWnd ,UINT wMessage,WPARAM wParam,LPARAM lParam)
{
PAINTSTRUCT ps;
HDC hDC;
POINT pt;
TEXTMETRIC tm;
static int nCurPos=0;
static char cBuf[128];
static int nwidth,nheight;
static HFONT hFont,hOldFont;

switch(wMessage)
{
case WM_CREATE:
CreateCaret(hWnd,NULL,10,10);
ShowCaret(hWnd);
SetCaretPos(0,0);
hDC=GetDC(hWnd);
GetTextMetrics(hDC,&tm);
ReleaseDC(hWnd,hDC);
nwidth=tm.tmAveCharWidth;
nheight=tm.tmHeight;
}
break;

switch(wMessage)
{
case WM_PAINT:

hDC=BeginPaint(hWnd,&ps);
SetTextColor(hDC,RGB(0,0,255));
TextOut(hDC,0,0,cBuf,lstrlen(cBuf));
SelectObject(hDC,hOldFont);
EndPaint(hWnd,&ps);
}
break;
case WM_CHAR:
if(nCurPos<127&&(IsCharAlphaNumeric((char)wParam)) )
{
cBuf[nCurPos++]=(char)wParam;
cBuf[nCurPos]=0;
InvalidateRect(hWnd,NULL,TRUE);
}
break;
case WM_KEYDOWN:
GetCaretPos(&pt);
switch(wParam)
{
case VK_LEFT:
pt.x-=nwidth;
break;
case VK_RIGHT:
pt.x+=nwidth;
break;
case VK_UP:
pt.y-=nheight;
break;
case VK_DOWN:
pt.y+=nheight;
break;
case VK_HOME:
pt.y=0;
pt.x=0;
break;
case VK_END:
pt.y=1;
pt.x=1;
break;
case VK_BACK:
if(nCurPos>0)
{
nCurPos--;
cBuf[nCurPos]=0;
InvalidateRect (hWnd,NULL,TRUE);
}
break;
SetCaretPos(pt.x,pt.y);
break;
}
case WM_DESTROY:
DestroyCaret();
PostQuitMessage(0);
break;
default:
return DefWindowProc (hWnd,wMessage,wParam,lParam);
}
return 0;
}

Your wndproc is falling through to WM_DESTROY whenever it gets a WM_KEYDOWN message due to the way you've wriiten your break statements and closing braces. This will allow text input (the only WM_KEYDOWN that has any effect on the text is VK_BACK) -

Code:

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long FAR PASCAL WndProc(HWND hWnd ,UINT wMessage,WPARAM wParam,LPARAM lParam)
{
        PAINTSTRUCT ps;
        HDC hDC;
        POINT pt;
        TEXTMETRIC tm;
        static int nCurPos=0;
        static char cBuf[128];
        static int nwidth,nheight;
        static HFONT hFont,hOldFont;

        switch(wMessage)
        {
        case WM_CREATE:
       
                CreateCaret(hWnd,NULL,10,10);
                ShowCaret(hWnd);
                SetCaretPos(0,0);
                hDC=GetDC(hWnd);
                GetTextMetrics(hDC,&tm);
                ReleaseDC(hWnd,hDC);
                nwidth=tm.tmAveCharWidth;
                nheight=tm.tmHeight;
                break;


        case WM_PAINT:

                hDC=BeginPaint(hWnd,&ps);
                SetTextColor(hDC,RGB(0,0,255));
                TextOut(hDC,0,0,cBuf,lstrlen(cBuf));
                SelectObject(hDC,hOldFont);
                EndPaint(hWnd,&ps);
                break;

        case WM_CHAR:
                if(nCurPos<127&&(IsCharAlphaNumeric((char)wParam)))
                {
                        cBuf[nCurPos++]=(char)wParam;
                        cBuf[nCurPos]=0;
                        InvalidateRect(hWnd,NULL,TRUE);
                }
                break;

        case WM_KEYDOWN:
                GetCaretPos(&pt);

                switch(wParam)
                {
                case VK_LEFT:
                        pt.x-=nwidth;
                        break;
                case VK_RIGHT:
                        pt.x+=nwidth;
                        break;
                case VK_UP:
                        pt.y-=nheight;
                        break;
                case VK_DOWN:
                        pt.y+=nheight;
                        break;
                case VK_HOME:
                        pt.y=0;
                        pt.x=0;
                        break;
                case VK_END:
                        pt.y=1;
                        pt.x=1;
                        break;
                case VK_BACK:
                        if(nCurPos>0)
                        {
                                nCurPos--;
                                cBuf[nCurPos]=0;
                                InvalidateRect (hWnd,NULL,TRUE);
                        }
                        break;
               
               
                }
                SetCaretPos(pt.x,pt.y);
                break;
       

                case WM_DESTROY:
                        DestroyCaret();
                        PostQuitMessage(0);
                        break;

                default:
                        return DefWindowProc (hWnd,wMessage,wParam,lParam);
}
return 0;
}

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