自动设置ComboxBox控件或ListBox控件 水平滚动条

// The pointer to my combo box.extern CComboBox* pmyComboBox;// Find the longest string in the combo box.CString str;CSize sz;int dx = 0;TEXTMETRIC tm;CDC* pDC = pmyComboBox->GetDC();CFont* pFont = pmyComboBox->GetFont();// Select the listbox font, save the old fontCFont* pOldFont = pDC->SelectObject(pFont);// Get the text metrics for avg char widthpDC->GetTextMetrics(&tm);for (int i = 0; i < pmyComboBox->GetCount(); i++){ pmyComboBox->GetLBText(i, str); sz = pDC->GetTextExtent(str); // Add the avg width to prevent clipping sz.cx += tm.tmAveCharWidth; if (sz.cx > dx) dx = sz.cx;}// Select the old font back into the DCpDC->SelectObject(pOldFont);pmyComboBox->ReleaseDC(pDC);// Set the horizontal extent so every character of all strings can // be scrolled to.pmyComboBox->SetHorizontalExtent(dx); 

来自MSDN