/// <summary>
/// Sorts the elements of a sequence in ascending order according to a key.
/// </summary>
/// <typeparam name="TKey">The type of the key returned by the function that is represented by keySelector.</typeparam>
/// <param name="keySelector">A function to extract a key from an element.</param>
/// <returns>A new query instance containing all specified query parameters.</returns>
public IOrderedQuery <T> OrderBy <TKey>(Expression <Func <T, TKey> > keySelector)
{
var expression = _expressionTranslator(keySelector);
var sortExpression = new Expressions.SortExpression(expression, Expressions.SortDirection.Ascending);
var query = new Query <T>(_dataProvider, _expressionTranslator, FilterExpressions, new[] { sortExpression }, SkipValue, TakeValue);
return(query);
}
/// <summary>
/// Performs a subsequent ordering of the elements in a sequence in descending order, according to a key.
/// </summary>
/// <typeparam name="TKey">The type of the key returned by the function represented by keySelector.</typeparam>
/// <param name="keySelector">A function to extract a key from each element.</param>
/// <returns>A new query instance containing all specified query parameters.</returns>
IOrderedQuery <T> IOrderedQuery <T> .ThenByDescending <TKey>(Expression <Func <T, TKey> > keySelector)
{
var sortExpressions = SortExpressions.AsEmptyIfNull().ToList();
if (!sortExpressions.Any())
{
throw new InvalidOperationException("No sorting defined yet, use OrderBy or OrderByDescending first.");
}
var expression = _expressionTranslator(keySelector);
var sortExpression = new Expressions.SortExpression(expression, Expressions.SortDirection.Descending);
sortExpressions.Add(sortExpression);
var query = new Query <T>(_dataProvider, _expressionTranslator, FilterExpressions, sortExpressions, SkipValue, TakeValue);
return(query);
}
