我们有一个包含大量数据的表,我不想为我的 dxDataGrid 一次加载它。
我想用 dxDataGrid 的 DataSourceLoadOptions 提供的 Skip / Take 实现分页。
这是我的控制器:
[HttpGet]
public async Task<Object> GetSalesOrdersWithTotals(DataSourceLoadOptions loadOptions)
{
try
{
var results = await SalesOrderService.GetSalesOrdersWithTotals(loadOptions.Skip, loadOptions.Take, 40);
loadOptions.Skip = 0;
loadOptions.Take = 0;
return DataSourceLoader.Load(results, loadOptions);
}
catch (Exception ex)
{
return Json(new { code = "422", success = false, message = "Unable to fetch sales orders with totals - " + ex.ToString() });
}
}
这是返回数据的服务:
public async Task<IEnumerable<SalesOrderWithTotals>> GetSalesOrdersWithTotals(int skip, int take, int defaultPageSize)
{
if (take == 0)
{
//Fix for passing a 0 take
take = defaultPageSize;
}
var salesOrderWithTotals =
from o in _context.SalesOrder
select new SalesOrderWithTotals
{
SalesOrderId = o.SalesOrderId,
Net = _context.SalesOrderItem.Where(it => it.SalesOrderId == o.SalesOrderId).Select(it => it.Qty == null ? 0 : it.Qty.Value * it.UnitPrice == null ? 0 : it.UnitPrice.Value).Sum(),
Tax = _context.SalesOrderItem.Where(it => it.SalesOrderId == o.SalesOrderId).Select(it => it.Qty == null ? 0 : it.Qty.Value * it.UnitPrice == null ? 0 : it.UnitPrice.Value).Sum() * (o.Tax.Percentage /100),
Gross = _context.SalesOrderItem.Where(it => it.SalesOrderId == o.SalesOrderId).Select(it => it.Qty == null ? 0 : it.Qty.Value * it.UnitPrice == null ? 0 : it.UnitPrice.Value).Sum() + _context.SalesOrderItem.Where(it => it.SalesOrderId == o.SalesOrderId).Select(it => it.Qty == null ? 0 : it.Qty.Value * it.UnitPrice == null ? 0 : it.UnitPrice.Value).Sum() * (o.Tax.Percentage / 100),
Name = o.Customer.Name,
CustomerOrderNumber = o.CustomerOrderNumber,
Contact = o.Contact,
OrderDate = o.OrderDate
};
return await salesOrderWithTotals.Skip(skip).Take(take).ToListAsync();
}
查看 SQL 探查器,这需要前 40 条记录,但 dxDataGrid 当然不知道记录的总数,因此分页不可用。
在这种情况下,实现我想要的最佳方法是什么?
非常感谢