英文:
C# IQueryable .Union reset sorting
问题
但是在 .Union 操作之后，排序被重置了。
如何防止排序被重置？
英文:
I have the following code:
var expressions = new List<IQueryable<Container>>();
var containers1 = containers
.Where(x => EF.Functions.Like(x.ContainerReference1, $"%{message.SearchValue}%")
|| EF.Functions.Like(x.ContainerReference2, $"%{message.SearchValue}%"))
.OrderBy(x => x.ContainerReference1)
.ThenBy(x => x.ContainerReference2)
.ThenByDescending(x => x.DateUpdated);
expressions.Add(containers1);
var containers2 = containers
.Where(x => EF.Functions.Like(x.Description, $"%{message.SearchValue}%"))
.OrderBy(x => x.Description)
.ThenByDescending(x => x.DateUpdated);
expressions.Add(containers2);
var containers3 = containers.Where(x => x.ContactEmails
.OrderBy(y => y.Email)
.ThenBy(y => y.DisplayName)
.Any(y => EF.Functions.Like(y.Email, $"%{message.SearchValue}%")
|| EF.Functions.Like(y.DisplayName, $"%{message.SearchValue}%")))
.OrderByDescending(x => x.DateUpdated);
expressions.Add(containers3);
var containers4 = containers
.Where(x => EF.Functions.Like(x.Keywords, $"%{message.SearchValue}%"))
.OrderBy(x => x.Keywords)
.ThenByDescending(x => x.DateUpdated);
expressions.Add(containers4);
containers = expressions.Aggregate((acc, i) => acc.Union(i));
But after .Union operation sorting is reset.
How can I prevent resetting of sorting?
答案1
得分: 1
Union 操作符不会保留元素的顺序。您需要根据数据的存在动态构建排序逻辑。
var expressions = new List<IQueryable<Container>>();
var sortingExpressions = new List<Func<IQueryable<Container>, IOrderedQueryable<Container>>>();
var containers1 = containers
.Where(x => EF.Functions.Like(x.ContainerReference1, $"%{message.SearchValue}%")
|| EF.Functions.Like(x.ContainerReference2, $"%{message.SearchValue}%"));
if (containers1.Any())
{
var containers1Sorting = new Func<IQueryable<Container>, IOrderedQueryable<Container>>(x => x
.OrderBy(y => y.ContainerReference1)
.ThenBy(y => y.ContainerReference2)
.ThenByDescending(y => y.DateUpdated));
expressions.Add(containers1);
sortingExpressions.Add(containers1Sorting);
}
var containers2 = containers
.Where(x => EF.Functions.Like(x.Description, $"%{message.SearchValue}%"));
if (containers2.Any())
{
var containers2Sorting = new Func<IQueryable<Container>, IOrderedQueryable<Container>>(x => x
.OrderBy(y => y.Description)
.ThenByDescending(y => y.DateUpdated));
expressions.Add(containers2);
sortingExpressions.Add(containers2Sorting);
}
var containers3 = containers
.Where(x => x.ContactEmails
.Any(y => EF.Functions.Like(y.Email, $"%{message.SearchValue}%")
|| EF.Functions.Like(y.DisplayName, $"%{message.SearchValue}%")));
if (containers3.Any())
{
var containers3Sorting = new Func<IQueryable<Container>, IOrderedQueryable<Container>>(x => x
.OrderBy(y => y.ContactEmails.OrderBy(z => z.Email).ThenBy(z => z.DisplayName))
.OrderByDescending(x => x.DateUpdated));
expressions.Add(containers3);
sortingExpressions.Add(containers3Sorting);
}
var containers4 = containers
.Where(x => EF.Functions.Like(x.Keywords, $"%{message.SearchValue}%"));
if (containers4.Any())
{
var containers4Sorting = new Func<IQueryable<Container>, IOrderedQueryable<Container>>(x => x
.OrderBy(y => y.Keywords)
.ThenByDescending(y => y.DateUpdated));
expressions.Add(containers4);
sortingExpressions.Add(containers4Sorting);
}
var mergedContainers = expressions.Aggregate((acc, i) => acc.Union(i));
if (sortingExpressions.Any())
{
var mergedSorting = sortingExpressions
.Aggregate((acc, next) => q => next(acc(q)));
containers = mergedSorting(mergedContainers);
}
else
{
containers = mergedContainers.OrderByDescending(x => x.DateUpdated);
}
英文:
Union operator does not preserve the order of the elements. You need to dynamically construct the sorting logic based on the presence of data
var expressions = new List<IQueryable<Container>>();
var sortingExpressions = new List<Func<IQueryable<Container>, IOrderedQueryable<Container>>>();
var containers1 = containers
.Where(x => EF.Functions.Like(x.ContainerReference1, $"%{message.SearchValue}%")
|| EF.Functions.Like(x.ContainerReference2, $"%{message.SearchValue}%"));
if (containers1.Any())
{
var containers1Sorting = new Func<IQueryable<Container>, IOrderedQueryable<Container>>(x => x
.OrderBy(y => y.ContainerReference1)
.ThenBy(y => y.ContainerReference2)
.ThenByDescending(y => y.DateUpdated));
expressions.Add(containers1);
sortingExpressions.Add(containers1Sorting);
}
var containers2 = containers
.Where(x => EF.Functions.Like(x.Description, $"%{message.SearchValue}%"));
if (containers2.Any())
{
var containers2Sorting = new Func<IQueryable<Container>, IOrderedQueryable<Container>>(x => x
.OrderBy(y => y.Description)
.ThenByDescending(y => y.DateUpdated));
expressions.Add(containers2);
sortingExpressions.Add(containers2Sorting);
}
var containers3 = containers
.Where(x => x.ContactEmails
.Any(y => EF.Functions.Like(y.Email, $"%{message.SearchValue}%")
|| EF.Functions.Like(y.DisplayName, $"%{message.SearchValue}%")));
if (containers3.Any())
{
var containers3Sorting = new Func<IQueryable<Container>, IOrderedQueryable<Container>>(x => x
.OrderBy(y => y.ContactEmails.OrderBy(z => z.Email).ThenBy(z => z.DisplayName))
.OrderByDescending(x => x.DateUpdated));
expressions.Add(containers3);
sortingExpressions.Add(containers3Sorting);
}
var containers4 = containers
.Where(x => EF.Functions.Like(x.Keywords, $"%{message.SearchValue}%"));
if (containers4.Any())
{
var containers4Sorting = new Func<IQueryable<Container>, IOrderedQueryable<Container>>(x => x
.OrderBy(y => y.Keywords)
.ThenByDescending(y => y.DateUpdated));
expressions.Add(containers4);
sortingExpressions.Add(containers4Sorting);
}
var mergedContainers = expressions.Aggregate((acc, i) => acc.Union(i));
if (sortingExpressions.Any())
{
var mergedSorting = sortingExpressions
.Aggregate((acc, next) => q => next(acc(q)));
containers = mergedSorting(mergedContainers);
}
else
{
containers = mergedContainers.OrderByDescending(x => x.DateUpdated);
}
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