c# - 尝试使用 IQueryable 自定义 OrderBy - "Skip"方法错误

Question

我的代码的第一部分获取 IQueryable 数据结果:

var issues = repository.GetAllIssues().Where(i => 
                  i.IssueNotificationRecipients.Any(r => r.Status == "Open"));

然后我确定用户请求的排序顺序，并添加它:

switch (sort)
{
case 1:
    issues.OrderBy(x => x.Customer);
    break;
case 2:
    issues.OrderBy(x => x.Description);
    break;
case 3:
    issues.OrderBy(x => x.CreatedBy);
    break;
default:
    issues.OrderBy(x => x.DueDateTime);
    break;
}

这会引发错误:

The method 'Skip' is only supported for sorted input in LINQ to Entities. The method 'OrderBy' must be called before the method 'Skip'

那么我如何动态添加 OrderBy 以响应用户的输入？

Answer 1

你的意思是

switch (sort)
{
case 1:
    issues = issues.OrderBy(x => x.Customer);
    break;
case 2:
    issues = issues.OrderBy(x => x.Description);
    break;
case 3:
    issues = issues.OrderBy(x => x.CreatedBy);
    break;
default:
    issues = issues.OrderBy(x => x.DueDateTime);
    break;
}

您可能需要更改 issues 的类型，或将其设置为新变量，因为它返回 IOrderedQueryable<T>