/// <summary>
/// 获得排序字段集合
/// </summary>
/// <param name="para"></param>
/// <returns></returns>
public static IReadOnlyDictionary <string, Direction> GetOrderings(this IODataParameter para)
{
if (para is ODataParameter opara)
{
return(opara.Orderings);
}
return(ODataParameter.ToOrderingDictionary(para.OrderBy));
}
/// <summary>
/// OData查询，支持 top, skip, orderby
/// </summary>
/// <typeparam name="T">数据源类型</typeparam>
/// <param name="query">数据源</param>
/// <param name="top">加载的数据量</param>
/// <param name="skip">跳过的数据量</param>
/// <param name="orderby">排序信息</param>
/// <returns>排序分页后的数据</returns>
public static IQueryable <T> ODataQuery <T>(this IQueryable <T> query, int top, int skip, string orderby)
{
IReadOnlyDictionary <string, Direction> orderings = ODataParameter.ToOrderingDictionary(orderby);
return(ODataQuery(query, top, skip, orderings));
}