C# · 12月 23, 2021

c# – 如何改进此排序代码?

我正在检查sort参数并构建一堆if语句: if (sortDirection == “ASC”){ if (sortBy == “Id”) return customerList.OrderBy(x => x.Id).Skip(startIndex).Take(pageSize).ToList(); if (sortBy == “FirstName”) return customerList.OrderBy(x => x.FirstName).Skip(startIndex).Take(pageSize).ToList(); if (sortBy == “City”) return customerList.OrderBy(x => x.City).Skip(startIndex).Take(pageSize).ToList();}else{ if (sortBy == “Id”) return customerList.OrderByDescending(x => x.Id).Skip(startIndex).Take(pageSize).ToList(); if (sortBy == “FirstName”) return customerList.OrderByDescending(x => x.FirstName).Skip(startIndex).Take(pageSize).ToList(); if (sortBy == “City”) return customerList.OrderByDescending(x => x.City).Skip(startIndex).Take(pageSize).ToList();}

我该如何做得更好?

解决方法 单独排序和查询的其余部分 – 对于您不必在代码库中复制的每个查询,相同的部分(保持 DRY): var query = customerList;if (sortDirection == “ASC”){ if (sortBy == “Id”) query = query.OrderBy(x => x.Id); ///and so on}query = query.Skip(startIndex).Take(pageSize).ToList();