使用Linq查询2套复杂对象

Question

I have two lists comprised of different complex-objects, and each one is from 2 separate data-sources. One list may-or-may-not contain records. When any records exist in the "optional" list I need the "normal" list to be further-filtered.

Unfortunately, I can only find very simple examples here and online, which is why I am asking this question.

The Pseudo-Logic Goes Like This:
When QuickFindMaterial records exist, get all DataSource records where query.Name is in the QuickFindMaterial.Material collection. If no QuickFindMaterial records exist do not affect the final result. Lastly, select all distinct DataSource records.

The Classes Looks Like:

public class QuickFindMaterial
{
    public string SiteId { get; set; }
    public string Material { get; set; }
}

The Code Looks Like:
I have commented-out my failed WHERE logic below

    var dataSource = DocumentCollectionService.ListQuickFind();
    var quickFindMaterial = ListMaterialBySiteID(customerSiteId);

    var distinct = (from query in dataSource
                                    select new
                                               {
                                                   ID = query.DocumentID,
                                                   Library = query.DocumentLibrary,
                                                   ModifiedDate = query.DocumentModifiedDate,
                                                   Name = query.DocumentName,
                                                   Title = query.DocumentTitle,
                                                   Type = query.DocumentType,
                                                   Url = query.DocumentUrl,
                                               })
//.Where(x => x.Name.Contains(quickFindMaterial.SelectMany(q => q.Material)))
//.Where(x => quickFindMaterial.Contains(x.Name))
.Distinct();

Answer 1

我认为这是您想要的：

.Where(x => !quickFindMaterial.Any() || quickFindMaterial.Any(y => x.Name == y.Material))

Answer 2

You could join on Name -> Material

Example:

   var distinct = (from query in dataSource
                        join foo in quickFindMaterial on query.Name equals foo.Material
                        select new
                                    {
                                        ID = query.DocumentID,
                                        Library = query.DocumentLibrary,
                                        ModifiedDate = query.DocumentModifiedDate,
                                        Name = query.DocumentName,
                                        Title = query.DocumentTitle,
                                        Type = query.DocumentType,
                                        Url = query.DocumentUrl,
                                    }).Distinct();