EditBoxに追記

CString csBuf;
CEdit* pEdit = (CEdit*)GetDlgItem(IDC_LOG);
DWORD dwEnd = ::GetTickCount();
csBuf.Format("%.3f\r\n", dwEnd/1000.0);
pEdit->SetSel(INT_MAX, INT_MAX);
pEdit->ReplaceSel(csBuf);

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