I was going through a tutorial and had some trouble with an example program. Here's the coding I have and I can't fix it.

Here is the main cpp file.

#include <windows.h>

#include "resource.h" 

BOOL CALLBACK DlgProc(HWND hwnd, UINT Message, WPARAM wParam, LPARAM lParam)
{
	switch(Message)
	{
		case WM_INITDIALOG:
			// This is where we set up the dialog box, and initialise any default values

			SetDlgItemText(hwnd, IDC_TEXT, "This is a string");
			SetDlgItemInt(hwnd, IDC_NUMBER, 5, FALSE);
		break;
		case WM_COMMAND:
			switch(LOWORD(wParam))
			{
				case IDC_ADD:
				{
					// When somebody clicks the Add button, first we get the number of
					// they entered

					BOOL bSuccess;
					int nTimes = GetDlgItemInt(hwnd, IDC_NUMBER, &bSuccess, FALSE);
					if(bSuccess) 
					{
						// Then we get the string they entered
						// First we need to find out how long it is so that we can
						// allocate some memory

						int len = GetWindowTextLength(GetDlgItem(hwnd, IDC_TEXT));
						if(len > 0)
						{
							// Now we allocate, and get the string into our buffer

							int i;
							char* buf;

							buf = (char*)GlobalAlloc(GPTR, len + 1);
							GetDlgItemText(hwnd, IDC_TEXT, buf, len + 1);

							// Now we add the string to the list box however many times
							// the user asked us to.

							for(i = 0;i < nTimes; i++)
							{
								int index = SendDlgItemMessage(hwnd, IDC_LIST, LB_ADDSTRING, 0, (LPARAM)buf);

								// Here we are associating the value nTimes with the item 
								// just for the heck of it, we'll use it to display later.
								// Normally you would put some more useful data here, such
								// as a pointer.
								SendDlgItemMessage(hwnd, IDC_LIST, LB_SETITEMDATA, (WPARAM)index, (LPARAM)nTimes);
							}

							// Dont' forget to free the memory!
							GlobalFree((HANDLE)buf);
						}
						else 
						{
							MessageBox(hwnd, "You didn't enter anything!", "Warning", MB_OK);
						}
					}
					else 
					{
						MessageBox(hwnd, "Couldn't translate that number :(", "Warning", MB_OK);
					}

				}
				break;
				case IDC_REMOVE:
				{
					// When the user clicks the Remove button, we first get the number
					// of selected items

					HWND hList = GetDlgItem(hwnd, IDC_LIST);
					int count = SendMessage(hList, LB_GETSELCOUNT, 0, 0);
					if(count != LB_ERR)
					{
						if(count != 0)
						{
							// And then allocate room to store the list of selected items.

							int i;
							int *buf = GlobalAlloc(GPTR, sizeof(int) * count);
							SendMessage(hList, LB_GETSELITEMS, (WPARAM)count, (LPARAM)buf);
							
							// Now we loop through the list and remove each item that was
							// selected.  

							// WARNING!!!  
							// We loop backwards, because if we removed items
							// from top to bottom, it would change the indexes of the other
							// items!!!

							for(i = count - 1; i >= 0; i--)
							{
								SendMessage(hList, LB_DELETESTRING, (WPARAM)buf[i], 0);
							}

							GlobalFree(buf);
						}
						else 
						{
							MessageBox(hwnd, "No items selected.", "Warning", MB_OK);
						}
					}
					else
					{
						MessageBox(hwnd, "Error counting items :(", "Warning", MB_OK);
					}
				}
				break;
				case IDC_CLEAR:
					SendDlgItemMessage(hwnd, IDC_LIST, LB_RESETCONTENT, 0, 0);
				break;
				case IDC_LIST:
					switch(HIWORD(wParam))
					{
						case LBN_SELCHANGE:
						{
							// Get the number of items selected.

							HWND hList = GetDlgItem(hwnd, IDC_LIST);
							int count = SendMessage(hList, LB_GETSELCOUNT, 0, 0);
							if(count != LB_ERR)
							{
								// We only want to continue if one and only one item is
								// selected.

								if(count == 1)
								{
									// Since we know ahead of time we're only getting one
									// index, there's no need to allocate an array.

									int index;
									int err = SendMessage(hList, LB_GETSELITEMS, (WPARAM)1, (LPARAM)&index);
									if(err != LB_ERR)
									{
										// Get the data we associated with the item above
										// (the number of times it was added)

										int data = SendMessage(hList, LB_GETITEMDATA, (WPARAM)index, 0);

										SetDlgItemInt(hwnd, IDC_SHOWCOUNT, data, FALSE);
									}
									else 
									{
										MessageBox(hwnd, "Error getting selected item :(", "Warning", MB_OK);
									}
								}
								else 
								{
									// No items selected, or more than one
									// Either way, we aren't going to process this.
									SetDlgItemText(hwnd, IDC_SHOWCOUNT, "-");
								}
							}
							else
							{
								MessageBox(hwnd, "Error counting items :(", "Warning", MB_OK);
							}
						}
						break;
					}
				break;
			}
		break;
		case WM_CLOSE:
			EndDialog(hwnd, 0);
		break;
		default:
			return FALSE;
	}
	return TRUE;
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
	LPSTR lpCmdLine, int nCmdShow)
{
	return DialogBox(hInstance, MAKEINTRESOURCE(IDD_MAIN), NULL, DlgProc);
}

Here is my header file.

//{{NO_DEPENDENCIES}}
// Microsoft Developer Studio generated include file.
// Used by ctl_one.rc
//
#define IDD_MAIN                        101
#define IDC_TEXT                        1000
#define IDC_NUMBER                      1001
#define IDC_LIST                        1002
#define IDC_ADD                         1003
#define IDC_CLEAR                       1004
#define IDC_REMOVE                      1005
#define IDC_SHOWCOUNT                   1006

// Next default values for new objects
// 
#ifdef APSTUDIO_INVOKED
#ifndef APSTUDIO_READONLY_SYMBOLS
#define _APS_NEXT_RESOURCE_VALUE        102
#define _APS_NEXT_COMMAND_VALUE         40001
#define _APS_NEXT_CONTROL_VALUE         1007
#define _APS_NEXT_SYMED_VALUE           101
#endif
#endif

And here is the resource file.

//Microsoft Developer Studio generated resource script.
//
#include "resource.h"

#define APSTUDIO_READONLY_SYMBOLS
/////////////////////////////////////////////////////////////////////////////
//
// Generated from the TEXTINCLUDE 2 resource.
//
#ifndef __BORLANDC__
#include "winres.h"
#endif

/////////////////////////////////////////////////////////////////////////////
#undef APSTUDIO_READONLY_SYMBOLS

/////////////////////////////////////////////////////////////////////////////
// English (U.S.) resources

#if !defined(AFX_RESOURCE_DLL) || defined(AFX_TARG_ENU)
#ifdef _WIN32
LANGUAGE LANG_ENGLISH, SUBLANG_ENGLISH_US
#pragma code_page(1252)
#endif //_WIN32

#ifdef APSTUDIO_INVOKED
/////////////////////////////////////////////////////////////////////////////
//
// TEXTINCLUDE
//

1 TEXTINCLUDE DISCARDABLE 
BEGIN
    "resource.h\0"
END

2 TEXTINCLUDE DISCARDABLE 
BEGIN
    "#ifndef __BORLANDC__\r\n"
    "#include ""winres.h""\r\n"
    "#endif\r\n"
    "\0"
END

3 TEXTINCLUDE DISCARDABLE 
BEGIN
    "\0"
END

#endif    // APSTUDIO_INVOKED


/////////////////////////////////////////////////////////////////////////////
//
// Dialog
//

IDD_MAIN DIALOG DISCARDABLE  0, 0, 207, 156
STYLE DS_MODALFRAME | DS_CENTER | WS_POPUP | WS_CAPTION | WS_SYSMENU
CAPTION "Controls One"
FONT 8, "MS Sans Serif"
BEGIN
    LTEXT           "Add",IDC_STATIC,7,10,14,8
    EDITTEXT        IDC_TEXT,25,7,120,14,ES_AUTOHSCROLL
    EDITTEXT        IDC_NUMBER,150,7,21,14,ES_NUMBER
    LTEXT           "times.",IDC_STATIC,177,10,23,8
    LISTBOX         IDC_LIST,7,25,138,106,LBS_NOINTEGRALHEIGHT | 
                    LBS_EXTENDEDSEL | WS_VSCROLL | WS_TABSTOP
    PUSHBUTTON      "&Add",IDC_ADD,150,30,50,14
    PUSHBUTTON      "&Remove",IDC_REMOVE,150,47,50,14
    PUSHBUTTON      "&Clear",IDC_CLEAR,150,63,50,14
    LTEXT           "This item was added",IDC_STATIC,7,141,66,8
    CTEXT           "-",IDC_SHOWCOUNT,77,141,32,8
    LTEXT           "times",IDC_STATIC,114,141,17,8
END


/////////////////////////////////////////////////////////////////////////////
//
// DESIGNINFO
//

#ifdef APSTUDIO_INVOKED
GUIDELINES DESIGNINFO DISCARDABLE 
BEGIN
    IDD_MAIN, DIALOG
    BEGIN
        LEFTMARGIN, 7
        RIGHTMARGIN, 200
        VERTGUIDE, 145
        VERTGUIDE, 150
        TOPMARGIN, 7
        BOTTOMMARGIN, 149
    END
END
#endif    // APSTUDIO_INVOKED

#endif    // English (U.S.) resources
/////////////////////////////////////////////////////////////////////////////

I keep getting this error:
1>c:\users\chris\desktop\word editor.cpp(85) : error C2440: 'initializing' : cannot convert from 'HGLOBAL' to 'int *'
1> Conversion from 'void*' to pointer to non-'void' requires an explicit cast

What's Len?

thats not the important thing..Just have a look at your GlobalAlloc..All you need to do is casting..

Thank you.I copied and pasted your code and it said that LEN was undeclared but I understand now.

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