Read excel file

[ado130]

Hello forum,
I have excel file with this pattern:

ID              #1  #2  #3
       NAME     A     B    C
#1      A       x
#2      B             x
#3      C       x

ID              #1  #2  #3
       NAME     A     B    C
#1      A       x
#2      B             x
#3      C       x

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"X" means that the row belongs to the column.

QString path = fileName;
    sheet = nullptr;
    sheets = nullptr;
    workbook = nullptr;
    workbooks = nullptr;
    excelApplication = nullptr;
 
    if(path == "")
    {
        qDebug() << "'fileName' is empty!";
        return;
    }
    path.replace("/", "\\");
 
    excelApplication = new QAxObject( "Excel.Application", 0 );
 
    if (excelApplication == nullptr)
        throw invalid_argument("Failed to initialize interop with Excel (probably Excel is not installed)");
 
    excelApplication->dynamicCall( "SetVisible(bool)", false ); // hide excel
    excelApplication->setProperty( "DisplayAlerts", 0); // disable alerts
 
    workbooks = excelApplication->querySubObject( "Workbooks" );
    workbook = workbooks->querySubObject( "Open(const QString&)", path );
    sheets = workbook->querySubObject( "Worksheets" );
 
...
...
 
for(int i=0; i<rowsCnt; ;++i)
   for(int j=0; j<colsCnt; ;++j)
      {
         QAxObject* cell = sheet->querySubObject( "Cells( int, int )", i, j);
         QVariant value = cell->dynamicCall( "Value()" );
         dataRow.append(value);
      }

QString path = fileName;
    sheet = nullptr;
    sheets = nullptr;
    workbook = nullptr;
    workbooks = nullptr;
    excelApplication = nullptr;

    if(path == "")
    {
        qDebug() << "'fileName' is empty!";
        return;
    }
    path.replace("/", "\\");

    excelApplication = new QAxObject( "Excel.Application", 0 );

    if (excelApplication == nullptr)
        throw invalid_argument("Failed to initialize interop with Excel (probably Excel is not installed)");

    excelApplication->dynamicCall( "SetVisible(bool)", false ); // hide excel
    excelApplication->setProperty( "DisplayAlerts", 0); // disable alerts

    workbooks = excelApplication->querySubObject( "Workbooks" );
    workbook = workbooks->querySubObject( "Open(const QString&)", path );
    sheets = workbook->querySubObject( "Worksheets" );

...
...

for(int i=0; i<rowsCnt; ;++i)
   for(int j=0; j<colsCnt; ;++j)
      {
         QAxObject* cell = sheet->querySubObject( "Cells( int, int )", i, j);
         QVariant value = cell->dynamicCall( "Value()" );
         dataRow.append(value);
      }

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It works fine, but the execution time is slow, especially at a larger table (200x200 or more).

My question is if exist faster way to read excel file.

Thanks for any advice!

[d_stranz]

If you could find a way to replace the calls to querySubObject() and dynamicCall() in the inner loop over the cells, that would probably speed things up considerably.

QAxObject is convenient, but if you can #import the Excel type libraries this would let you use the Excel COM objects directly without all the parsing overhead. Here's a link that might help.

[ado130]

Thank you! I'll try the second option.