一个CListBox的横向滚动问题！

[kp]

请问怎么才能使CListBox具有横向滚动功能？
或者用AddString添加的数据能自动换行？

[kp]

哈哈，看来我只有自己解决问题了！
int CListBoxEx::AddString(LPCTSTR lpszItem)
{

LONG lStringExtent = GetExtentForString(lpszItem);
if(GetHorizontalExtent() < lStringExtent)
SetHorizontalExtent(lStringExtent);

return CListBox::AddString(lpszItem);
}

int CListBoxEx::DeleteString( UINT nIndex )
{
int nCountLeft=CListBox::DeleteString(nIndex);
if (nCountLeft== LB_ERR)
return LB_ERR;

LONG lMaxExtent=GetExtentForEntireControl();
SetHorizontalExtent(lMaxExtent);

return nCountLeft;
}

int CListBoxEx::InsertString( int nIndex, LPCTSTR lpszItem )
{
int nInsertPos=InsertString(nIndex, lpszItem);
if (nInsertPos== LB_ERR)
return LB_ERR;

LONG lStringExtent=GetExtentForString(lpszItem);
if(GetHorizontalExtent() < lStringExtent)
SetHorizontalExtent(lStringExtent);

return nInsertPos;
}

void CListBoxEx::ResetContent()
{
SetHorizontalExtent(0);
CListBox::ResetContent(); return;
}

int CListBoxEx::Dir( UINT attr, LPCTSTR lpszWildCard )
{
int nReturn=Dir(attr, lpszWildCard );
if (nReturn== LB_ERR || nReturn== LB_ERRSPACE)
return nReturn;

LONG lMaxExtent=GetExtentForEntireControl();
SetHorizontalExtent(lMaxExtent);
return nReturn;
}
LONG CListBoxEx::GetExtentForString(LPCTSTR lpszItem)
{
CDC* cdc=this->GetDC();
CFont* font = this->GetFont();
CFont* pOldFont;

if (font)
{
pOldFont = cdc->SelectObject(font);

TEXTMETRIC tm;
cdc->GetTextMetrics(&tm);

CSize size = cdc->GetTextExtent(lpszItem, lstrlen(lpszItem) );
size.cx += tm.tmAveCharWidth;

cdc->SelectObject(pOldFont);
this->ReleaseDC(cdc);

return (LONG) size.cx;
}

this->ReleaseDC(cdc);

return 0L;
}

long CListBoxEx::GetExtentForEntireControl()
{
CDC* cdc = this->GetDC();
CFont* font = this->GetFont();
CFont* pOldFont;
if (font)
{
pOldFont = cdc->SelectObject(font);
TEXTMETRIC tm;
cdc->GetTextMetrics(&tm);
CString sText;
LONG max_cx = 0;

for(int n = 0; n<GetCount(); n++)
{
this->GetText(n, sText);
if (sText == "")
continue;
CSize size = cdc->GetTextExtent(sText, sText.GetLength());
size.cx += tm.tmAveCharWidth;
if(max_cx <= size.cx)
max_cx = size.cx;
}
cdc->SelectObject(pOldFont);
this->ReleaseDC(cdc);
return max_cx;
}
this->ReleaseDC(cdc);
return 0L;
}

[Badwood]

不用那么复杂吧?给listbox发送一个消息就可以了,曾在delphi下做成过.