c++ - problem initializing global variables -

i have begun learning win32 api using tutorial:

http://www.winprog.org/tutorial/ (though i'm using c++, not c in tutorial) i'm experimenting "edit box"-function i'm trying compare text written in edit box line of characters. code:

#define idc_main_edit   101 

code:

case wm_create: {     hfont hfdefault;     hwnd hedit;      hedit = createwindowex(ws_ex_clientedge, "edit", "",          ws_child | ws_visible | ws_vscroll | ws_hscroll | es_multiline | es_autovscroll | es_autohscroll,          0, 0, 100, 100, hwnd, (hmenu)idc_main_edit, getmodulehandle(null), null);     if(hedit == null)         messagebox(hwnd, "could not create edit box.", "error", mb_ok | mb_iconerror);      hfdefault = getstockobject(default_gui_font);     sendmessage(hedit, wm_setfont, (wparam)hfdefault, makelparam(false, 0)); } break; case wm_size: {     hwnd hedit;     rect rcclient;      getclientrect(hwnd, &rcclient);      hedit = getdlgitem(hwnd, idc_main_edit);     setwindowpos(hedit, null, 0, 0, rcclient.right, rcclient.bottom, swp_nozorder); } break; 

code:

bool comparison (hwnd hedit) { lpwstr psztext; dword dwtextlength; dword dwbuffersize;  dwtextlength = getwindowtextlength(hedit); dwbuffersize = dwtextlength + 1;  getwindowtext(hedit, psztext, dwbuffersize);  if(psztext == text("3")) {     return true; } else {     return false; } } 

the problem when call "comparison"-function psztext , hedit aren't initialized. why psztext isn't , i've tried using new/delete fix it, don't work. have no clue hedit. perhaps using getwindowtext-function wrong? warnings code:

warning c4700: uninitialized local variable 'psztext' used warning c4700: uninitialized local variable 'hedit' used

run-time check failure (appear when i'm using function, , 1 of them) code:

run-time check failure #3 - variable 'hedit' being used without being initializ

psztext pointer type. you'need allocate memory before use it.

do this:

wchar_t *psztext = new wchar_t[size]; //calculate or guess `size`