What will be the best Utility function to Get Value from sql data reader ado.net?

What will be best way to Get Value from Sql Data reader?

I wrote a utility function to retrieve Value by column Name in underlying data type , anyone please suggest improvements in it.

The thing i consider inefficient is giving implementation for each type separately which will leave many types un handled,

Can My Code give compile type error for types which I did not handled? I considered using Generic Constraints but they are not help full in my case.

public static T GetValue<T>(SqlDataReader reader, string columnName,T defaultValue=default(T))
    {
        int ordinal;
        //checking whether column name exist in reader result set
        try
        {
            ordinal = reader.GetOrdinal(columnName);
        }
        catch (IndexOutOfRangeException coulmnException)
        {
            var innerexception =
                new IndexOutOfRangeException(
                                              String.Format("Coulumn Name does not exist in specified sql reader, {0}", coulmnException.Message),
                                              coulmnException
                                             );

            throw innerexception;
        }
        catch (Exception e)
        {
            throw e;
        }

        //Defining Types and their crossponding functions to be called.
        var typeDictionary = new Dictionary<Type, Func<T>>
            {
                {typeof(Int16), () => (T)Convert.ChangeType(reader.GetInt16(ordinal),typeof(T))},
                {typeof(Int32), () => (T)Convert.ChangeType(reader.GetInt32(ordinal),typeof(T))},
                {typeof(Int64), () => (T)Convert.ChangeType(reader.GetInt64(ordinal),typeof(T))},
                {typeof(String), () => (T)Convert.ChangeType(reader.GetString(ordinal),typeof(T))},
                {typeof(Boolean), () => (T)Convert.ChangeType(reader.GetBoolean(ordinal),typeof(T))},
                {typeof(Byte), () => (T)Convert.ChangeType(reader.GetByte(ordinal),typeof(T))},
                {typeof(DateTime), () => (T)Convert.ChangeType(reader.GetDateTime(ordinal),typeof(T))},
                {typeof(Char), () => (T)Convert.ChangeType(reader.GetChar(ordinal),typeof(T))},
                {typeof(Decimal), () => (T)Convert.ChangeType(reader.GetDecimal(ordinal),typeof(T))},
                {typeof(Double), () => (T)Convert.ChangeType(reader.GetDouble(ordinal),typeof(T))}
            };

        Type providedType = typeof (T);

        //Handling Nullable Types, If programmer wants to pass null value as default he should pass struct type with '?'.
        if (providedType.IsGenericType && providedType.GetGenericTypeDefinition() == typeof (Nullable<>))
        {
            providedType = Nullable.GetUnderlyingType(providedType);
        }

        if (typeDictionary[providedType]==null)
        {
            throw new ArgumentException("Not Supported Type");
        }

        var resultedValue = reader.IsDBNull(ordinal) ? defaultValue : typeDictionary[typeof (T)]();

        return resultedValue;
    }

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