title: How to insert null value for numeric field of a datatable in c#?
body: <p>Consider My dynamically generated datatable contains the following fileds <code>Id,Name,Mob1,Mob2</code></p>
  
  <p>If my datatable has this it get inserted successfully,</p>
  
  <pre><code>Id Name Mob1        Mob2
  1  acp  9994564564  9568848526
  </code></pre>
  
  <p>But when it is like this it gets failed saying,</p>
  
  <pre><code>Id Name Mob1        Mob2
  1  acp  9994564564  
  </code></pre>
  
  <p><code>The given value of type String from the data source cannot be converted to type decimal of the specified target column.</code></p>
  
  <p>I generating my datatable by readingt a csv file,</p>
  
  <pre><code>    CSVReader reader = new CSVReader(CSVFile.PostedFile.InputStream);
      string[] headers = reader.GetCSVLine();
      DataTable dt = new DataTable();
      foreach (string strHeader in headers)
      {
          dt.Columns.Add(strHeader);
      }
      string[] data;
      while ((data = reader.GetCSVLine()) != null)
      {
          dt.Rows.Add(data);
      }
  </code></pre>
  
  <p>Any suggestion how to insert null value for numeric field during BulkCopy in c#...</p>
  
  <p><strong>EDIT:</strong></p>
  
  <p>I tried this <code>dt.Columns["Mob2"].AllowDBNull = true;</code> but it doesn't seem to work...</p>