想要一个查询在 Linq 查询中按变量排序

本文介绍了想要一个查询在 Linq 查询中按变量排序的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

如何按列变量排序，因为我在页面上有一个下拉列表，我想根据此下拉列表中选择的排序显示网格，例如价格、代码、评级、描述等，我不想单独编写查询每一列.

How to make order by Column variable because I have a dropdown on page and I want to show grid according to sord order selected in this Dropdown e.g Price, Code, rating, description etc etc. and I donot want to write a separate query for each column.

from lm in lDc.tbl_Products where lm.TypeRef == pTypeId orderby lm.Code ascending select new;

推荐答案

假设您想通过 SQL 进行排序，那么您需要传入排序列/类型.查询会推迟到您实际执行选择之后，以便您可以分步构建查询，完成后像这样执行:

Assuming you want to do the sorting via SQL then you will need to pass in the sort column/type. The query is deferred until you actually do the select so you can build up the query in steps and once you are done execute it like so:

// Do you query first. This will NOT execute in SQL yet. var query = lDC.tbl_Products.Where(p => p.TypeRef == pTypeId); // Now add on the sort that you require... you could do ascending, descending, // different cols etc.. switch (sortColumn) { case "Price": query = query.OrderBy(q => q.Price); break; case "Code": query = query.OrderBy(q => q.Code); break; // etc... } // Now execute the query to get a result var result = query.ToList();

如果您想在 SQL 之外执行此操作，则只需获得不进行排序的基本结果，然后根据您需要的排序条件将 OrderBy 应用于结果.

If you want to do it outside of SQL then just get a basic result with no sorting and then apply an OrderBy to the result base on the sort criteria you need.