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CComboBox::GetHorizontalExtent

Retrieves from the combo box the width in pixels by which the list-box portion of the combo box can be scrolled horizontally.

UINT GetHorizontalExtent( ) const;

Return Value

The scrollable width of the list-box portion of the combo box, in pixels.

Remarks

This is applicable only if the list-box portion of the combo box has a horizontal scroll bar.

Example

// Find the longest string in the combo box.
CString strText;
CSize   sz;
UINT    dxText = 0;
CDC*    pDCCombo = m_pComboBox->GetDC();
for (int i = 0; i < m_pComboBox->GetCount(); i++)
{
   m_pComboBox->GetLBText(i, strText);
   sz = pDCCombo->GetTextExtent(strText);

   if (sz.cx > (LONG)dxText)
     dxText = sz.cx;
}
m_pComboBox->ReleaseDC(pDCCombo);

// Set the horizontal extent only if the current extent is not large enough. 
if (m_pComboBox->GetHorizontalExtent() < dxText)
{
   m_pComboBox->SetHorizontalExtent(dxText);
   ASSERT(m_pComboBox->GetHorizontalExtent() == dxText);
}

Requirements

Header: afxwin.h

See Also

Reference

CComboBox Class

Hierarchy Chart

CListBox::SetHorizontalExtent

CB_GETHORIZONTALEXTENT