public static IQueryable <T> SortQuery <T>(BasePagingRequest model, IQueryable <T> query, Boolean isSearchByCreatedAtDesc = false) where T : class
{
if (!query.HasElement())
{
return(query);
}
if (model.SortNames.HasElement() && !model.SortNames.Any(s => s.IsNullOrEmpty()) && model.SortDirections.HasElement() && model.SortNames.Count == model.SortDirections.Count)
{
for (int i = 0; i < model.SortNames.Count; i++)
{
string direction = model.SortDirections[i].ToString();
if (i != 0)
{
direction = direction.Replace("Order", "Then");
}
var exp = LinqHelper.GenerateMethodCall <T>(query, direction, model.SortNames[i]);
query = query.Provider.CreateQuery <T>(exp);
}
}
else
{
// if class default has not field createdAt, it not do any thing
var propertyInfo = query.First().GetType().GetProperty("CreatedAt", BindingFlags.IgnoreCase | BindingFlags.Public | BindingFlags.Instance);
if (propertyInfo != null)
{
if (isSearchByCreatedAtDesc)
{
query = query.OrderByDescending(e => propertyInfo.GetValue(e, null));
}
else
{
query = query.OrderBy(e => propertyInfo.GetValue(e, null));
}
}
}
return(query);
}
/// <summary>
/// 实现对数据的分页查询
/// </summary>
/// <param name="whereLambda">查询条件</param>
/// <param name="total">总条数</param>
/// <param name="pageIndex">当前第几页</param>
/// <param name="pageSize">一页显示多少条数据</param>
/// <param name="order">DESC/ASC</param>
/// <param name="sort">排序字段</param>
/// <returns></returns>
public BasePagingResponse <TResult> LoadPaging <TResult>(Expression <Func <T, bool> > whereLambda, Expression <Func <T, TResult> > selector, BasePagingRequest request) where TResult : BaseItemResponse
{
var result = _repository.LoadPaging(whereLambda, selector, out int total, request.PageIndex, request.PageSize, request.Direction, request.SortField);
var resultItems = result.ToList();
return(new BasePagingResponse <TResult>
{
Count = total,
Total = total % request.PageSize == 0 ? total / request.PageSize : total / request.PageSize + 1,
Items = resultItems
});
}
/// <summary>
/// 实现对数据的分页查询
/// </summary>
/// <param name="whereLambda">查询条件</param>
/// <param name="total">总条数</param>
/// <param name="pageIndex">当前第几页</param>
/// <param name="pageSize">一页显示多少条数据</param>
/// <param name="order">DESC/ASC</param>
/// <param name="sort">排序字段</param>
/// <returns></returns>
public async Task <TResult> GetListPagingAsync <TSelect, TResult>(Expression <Func <T, TSelect> > selector, Expression <Func <T, bool> > whereLambda, BasePagingRequest request) where TSelect : BaseItemResponse where TResult : BasePagingResponse <TSelect>, new()
{
var result = await _repository.GetListPagingAsync(whereLambda, selector, request.PageIndex, request.PageSize, request.Direction, request.SortField);
return(new TResult
{
Count = result.Count,
Total = result.Total,
Items = result.Items
});
}