case WM_INITDIALOG:
{
HDC hdc;
int i;
TCHAR str[100];
for(i = 0; i < 100; i++)
{
wsprintf(str, "This is a very very very very very long sentence - line %d", i + 1);
SendDlgItemMessage(hDlg, IDC_LIST, LB_ADDSTRING, 0, (LPARAM)str);
}
SendDlgItemMessage(hDlg, IDC_LIST, LB_SETHORIZONTALEXTENT, 500, 0);
// 设置长度为500像素的水平滚动条
}
break;