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POError: "bad variable type" in CComVariant::Copy when iterating through CComSafeArray
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  1. POError: "bad variable type" in CComVariant::Copy when iterating through CComSafeArray
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    copied!<pre><code>CComSafeArray&lt;VARIANT&gt; fields; hr = _tab_file-&gt;get_Fields(fields.GetSafeArrayPtr()); for ( LONG i = fields.GetLowerBound(), ie = fields.GetUpperBound(); i &lt;= ie; ++i) { CComVariant fld = fields.GetAt(i); // (1) raises DISP_E_BADVARTYPE (0x80020008L) // Next code works fine CComQIPtr&lt;ITabField&gt; field = fields.GetAt(i).punkVal; // (2) Ok _bstr_t fieldName; hr = field-&gt;get_Name(fieldName.GetAddress()); ::OutputDebugString(fieldName + _T("\n")); // Ok } </code></pre> <p>Line (1): <code>fields.GetAt(i)</code> returns <code>CComVariant</code>. When I try to assign this value to <code>CComVariant fld</code> called copy constructor and method <code>CComVariant::Copy</code> inside the copy constructor. It raise an exception ("bad variable type", <code>DISP_E_BADVARTYPE (0x80020008L)</code>). At the same time the line (2) works well. What's wrong with line (1), and how to fix it.</p> <p><strong>EDIT:</strong> This is code for <code>get_Field</code> (filling <code>SAFEARRAY</code>).</p> <pre><code>STDMETHODIMP TabFile::get_Fields( SAFEARRAY** fields ) { if(mapInfoFile_ == 0) return E_UNEXPECTED; int fieldCount = getFieldCount(); SAFEARRAY* arr = ::SafeArrayCreateVector(VT_UNKNOWN, 0, fieldCount); for(LONG i = 0; i &lt; fieldCount; i++) { QField* field = getQField(i); ITabField* tabField = TabField::CreateInstance(); tabField-&gt;put_Name(_bstr_t(field-&gt;GetNameRef())); tabField-&gt;put_Type(field-&gt;GetNativeFieldType(i)); ::SafeArrayPutElement(arr, &amp;i, tabField); tabField-&gt;Release(); } *fields = arr; return S_OK; } </code></pre>
 

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