Linq Include and Where Clause

Question

I have the following linq statement:

var result = _context.Settings
                     .Include(x => x.Files)
                     .Where(y => y.Files.Where(f => f.SettingFile == true))
                     .Select(z => z.Deleted == null)
                     .ToList();

The thing I want to do is to get all the settings from the table. I also want to include the files-table and get all the files that has the SettingFile true. But I keep get the following error:

Cannot implicity convert type IEnumerable(UploadedFile) to bool.

Here Is my UploadedFile-model:

[Required]
public string FileName { get; set; }
[Required]
public string FileExtension { get; set; }
[Required]
public byte[] FileContent { get; set; }

public Guid? FormAnswerId { get; set; }
public Guid? LicenseHolderId { get; set; }
public Guid? CaseId { get; set; }
public Guid? ErrandId { get; set; }
public bool SettingFile { get; set; }

Here is my Setting-model:

    public class Setting : ModelBase
{
    public string Key { get; set; }
    public string DisplayName { get; set; }
    public string DisplayText { get; set; }
    public string DisplayTab { get; set; }
    public string Value { get; set; }
    public string Type { get; set; }
    public virtual ICollection<UploadedFile> Files { get; set; }
}

Modelbase:

public abstract class ModelBase : EntityBase
{
   public DateTime? Deleted {get; set;}
}

What am I doing wrong with my query?

Answer 1

I don't quite understand what you're trying to accomplish, but I can explain your issue.

A Where() clause is a Func<T, bool> . You pass in an instance of T and it returns a bool value.

In this line .Where(y => y.Files.Where(f => f.SettingFile == true)) , you're returning a IEnumerable<T> where it should be returning a bool . This is what's causing the error. You can resolve the error by changing the y.Files.Where(f => f.SettingFile == true) to y.Files.Any(f => f.SettingFile) or y.Files.All(f => f.SettingFile) . However, I don't think this is what you're trying to accomplish.

Edit: Since you're trying to get all the Settings that have the SettingFile == true then do the following:

_context.Settings
        .Include(x => x.Files.Where(f => f.SettingFile == true))
        .Select(z => z.Deleted == null)
        .ToList();

Edit: After further communication in the comments, you said you wanted a collection of Setting . So you'll just need to remove the .Select(x => z.Deleted == null) and you should be golden.

_context.Settings
        .Include(x => x.Files.Where(f => f.SettingFile == true))
        .ToList();

I don't know your use case, but it might be advisable to add another Where condition to exclude any Settings that don't have Files where the SettingFile is true .

_context.Settings
        .Include(x => x.Files.Where(f => f.SettingFile == true))
        .Where(x => x.Files.Any(f => f.SettingFile == true))
        .ToList();