Implement GetFieldType(string). Fixes #440

Author: bgrainger

src/MySqlConnector/MySql.Data.MySqlClient/MySqlDataReader.cs

@@ -207,6 +207,7 @@ public override long GetChars(int ordinal, long dataOffset, char[] buffer, int b
 
 		public override string GetDataTypeName(int ordinal) => GetResultSet().GetDataTypeName(ordinal);
 
+		public Type GetFieldType(string name) => GetFieldType(GetOrdinal(name));
 		public override Type GetFieldType(int ordinal) => GetResultSet().GetFieldType(ordinal);
 
 		public override object GetValue(int ordinal) => GetResultSet().GetCurrentRow().GetValue(ordinal);

tests/SideBySide/DataTypes.cs

@@ -1013,6 +1013,7 @@ private void DoQuery<TException>(
 							{
 								Assert.Equal(value, reader.GetValue(0));
 								Assert.Equal(value.GetType(), reader.GetFieldType(0));
+								Assert.Equal(value.GetType(), reader.GetFieldType(column.Replace("`", "")));
 							}
 
 							// test `reader.GetFieldValue<value.GetType()>`