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DataRow: Select cell value by a given column name

ayi

I have a problem with a DataRow that I’m really struggling with.
The datarow is read in from an Excel spreadsheet using an OleDbConnection.
If I try to select data from the DataRow using the column name, it returns DBNull even though there is data there.
But it’s not quite that simple.
<code>datarow.Table.Columns[5].ColumnName</code> returns “my column”.
<code>datarow["my column"]</code> returns DBNull.
<code>datarow[5]</code> returns 500.
<code>datarow[datarow.Table.Columns[5].ColumnName]</code> returns DBNull. (just to make sure its not a typo!)
I could just select things from the datarow using the column number, but I dislike doing that since if the column ordering changes, the software will break.

ayi_2

Which version of .NET are you using? Since .NET 3.5, there’s an assembly System.Data.DataSetExtensions, which contains various useful extensions for dataTables, dataRows and the like.
You can try using
<pre><code class="lang-auto">row.Field<type>("fieldName");

</code></pre>
if that doesn’t work, you can do this:
<pre><code class="lang-auto">DataTable table = new DataTable();
var myColumn = table.Columns.Cast<DataColumn>().SingleOrDefault(col => col.ColumnName == "myColumnName");
if (myColumn != null)
{
// just some roww
var tableRow = table.AsEnumerable().First();
var myData = tableRow.Field<string>(myColumn);
// or if above does not work
myData = tableRow.Field<string>(table.Columns.IndexOf(myColumn));
}

</code></pre>