Export Ruby on Rails HTML table to .xls file

Question

I have the following table:

<tr>
    <th colspan = "18">  student info</th>
    <th colspan="10">class info</th>

</tr>


 <tr>
        <th colspan="1">First Name</th>
        <th colspan="1">Middle Name</th>
        <th colspan="1">Last Name</th>

        ....
</tr>

<tr>
          <td colspan="1"><%= link_to student.first_name,:controller => 'acme_modificationss' , :action=>'profile', :id => student.id %></td>
          <td colspan="1"><%= student.middle_name %></td>
          <td colspan="1"><%= student.last_name %></td>
          <td colspan="1"><%= student.first_name %></td>
          <td colspan="1"><%=m_first_name%></td>

.....

I need to export the same table to .xls file. So I added a new action to the controller:

    def document_xls
             ....
        respond_to do |format|
          format.xls

        end

      end

Then I added document_xls view:

<?xml version="1.0"?>
<Workbook xmlns="urn:schemas-microsoft-com:office:spreadsheet"
          xmlns:o="urn:schemas-microsoft-com:office:office"
          xmlns:x="urn:schemas-microsoft-com:office:excel"
          xmlns:ss="urn:schemas-microsoft-com:office:spreadsheet"
          xmlns:html="http://www.w3.org/TR/REC-html40">
    <Worksheet ss:Name="Sheet1">
        <Table>
          <Row>
                <Cell><Data ss:Type="String">Student Info</Data></Cell>
                <Cell><Data ss:Type="String">Class info</Data></Cell>
             ....
            </Row>
            <Row>
                <Cell><Data ss:Type="String">First Name</Data></Cell>
                <Cell><Data ss:Type="String">Middle Name</Data></Cell>
                <Cell><Data ss:Type="String">Last Name</Data></Cell>
...

This generates a file with type file. But I want to generate this file as .xls, so I tried to add this to my controller action:

  format.xls{ send_data @students, :type => 'application/vnd.ms-excel', :filename => 'students.xls' }

But I got this error:

NoMethodError (undefined method `bytesize' for #)

Also, I need the excel table headers to be merged in more than one cell, is there a way to do this?

Answer 1

One easier way to fix this is send content as HTML to excel. Excel is able to parse it and convert by his own, you just need to send the right headers. first, have your table in a partial view, then, in your controller create a method like this:

  def export
    headers['Content-Type'] = "application/vnd.ms-excel"
    headers['Content-Disposition'] = 'attachment; filename="report.xls"'
    headers['Cache-Control'] = ''
    @data = self.send params[:type]
    render layout: false
  end

3 first lines export the excel file, so, the next line send the data receiving like type method the name of the method that retrieve your data to html and excel view, and render: false show you an empty layout jus loading your data.

in your routes something like

get 'excel/stats/:type', to: 'stats#export', as: 'excel_stat'

In this example we have the stats controller with many different types of stats, and in a view 'export' in your controller, you can render the partial view like this

export.html.haml :

= render params[:type]