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copied!<p>You can't just test reader["field"] for null or DBNull because a IndexOutOfRangeException is thrown if the column isn't in the reader.</p> <p>The code I use in my mapping layer for creating domain objects and the stored procedures that use the mapping layer might have different column names is below; you could modify it to not throw an exception if the column isn't found and return default(t) or null.</p> <p>I understand this isn't the most elegant or optimal solution (and really, if you can avoid it then you should), however, legacy stored procedures or Sql queries might warrant a work-around.</p> <pre><code> /// <summary> /// Grabs the value from a specific datareader for a list of column names. /// </summary> /// <typeparam name="T">Type of the value.</typeparam> /// <param name="reader">Reader to grab data off of.</param> /// <param name="columnNames">Column names that should be interrogated.</param> /// <returns>Value from the first correct column name or an exception if none of the columns exist.</returns> public static T GetColumnValue<T>(IDataReader reader, params string[] columnNames) { bool foundValue = false; T value = default(T); IndexOutOfRangeException lastException = null; foreach (string columnName in columnNames) { try { int ordinal = reader.GetOrdinal(columnName); value = (T)reader.GetValue(ordinal); foundValue = true; } catch (IndexOutOfRangeException ex) { lastException = ex; } } if (!foundValue) { string message = string.Format("Column(s) {0} could not be not found.", string.Join(", ", columnNames)); throw new IndexOutOfRangeException(message, lastException); } return value; } </code></pre>

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