title: Creating a txt file from strings in a column R
body: <p>I have this table</p>
  <div class="s-table-container">
  <table class="s-table">
  <thead>
  <tr>
  <th>Column A</th>
  <th>Column B</th>
  <th>Column C</th>
  <th>Column D</th>
  </tr>
  </thead>
  <tbody>
  <tr>
  <td>A</td>
  <td>x</td>
  <td>1</td>
  <td>k1</td>
  </tr>
  <tr>
  <td>B</td>
  <td>k</td>
  <td>2</td>
  <td>k2</td>
  </tr>
  <tr>
  <td>C</td>
  <td>z</td>
  <td>3</td>
  <td>k3</td>
  </tr>
  <tr>
  <td>D</td>
  <td>y</td>
  <td>4</td>
  <td>k4</td>
  </tr>
  </tbody>
  </table>
  </div>
  <p>I would like to print a txt file containing all the string in column A, divided by comma.
  Output:
  txt file --&gt; A,B,C,D</p>
  <pre><code>df1 &lt;- structure(list(ColumnA = c(&quot;A&quot;, &quot;B&quot;, &quot;C&quot;, &quot;D&quot;), ColumnB = c(&quot;x&quot;, 
  &quot;k&quot;, &quot;z&quot;, &quot;y&quot;), ColumnC = 1:4, ColumnD = c(&quot;k1&quot;, &quot;k2&quot;, &quot;k3&quot;, 
  &quot;k4&quot;)), class = &quot;data.frame&quot;, row.names = c(NA, -4L))
  </code></pre>