Changing the datatype of column in datatable changes the cell text
<p>Ok, I start off by importing an excel file and then save the data into Data table and then putting it into Gridview. I wanted to copy the column header name into a row cell and it was giving error that Input string was not is a correct format. I tried changing the column data type and it works. But the data copied is different to the original. Here is the code I am using: </p>

<pre><code>DataTable dtf1 = new DataTable();
 OleDbDataAdapter adapter = new OleDbDataAdapter(sql, con);
adapter.FillSchema(dtf1, SchemaType.Source);
            dtf1.Columns[6].DataType = typeof(string);
            adapter.Fill(dtf1);

 dtf1.Rows[0][6] = dtf1.Columns[6].ColumnName.ToString();
</code></pre>

<p>The original data is a postcode number "3210" but it is copying it as something "F7".</p>
