LINQ Query if condition external parameter

Question

I'm trying to use LINQ to get a list of values.

I have code like this:

var _context = _scope.ServiceProvider.GetRequiredService<VMContext>();

if (boolparameter)
{
    var listCE = _context.Ce
                         .Where(x => x.VuId == element.VuId)
                         .Where(x => x.Score == 8)
                         .AsNoTracking()
                         .ToList();
}
else
{
    var listCE = _context.Ce
                         .Where(x => x.VuId == element.VuId)
                         .AsNoTracking()
                         .ToList();
}

Depends on boolparameter, I do a query or another one. Is there a way to use a single query with a conditions inside? Something like:

var listCE = _context.Ce
                     .Where(x => x.VuId == element.VuId)
                     .Where(x => boolparameter ? x.Score == 8 : true)
                     .AsNoTracking()
                     .ToList();

C# Asp.NetCore SqlServer 2019 Thanks a lot!

Answer 1

You could try the following code if it works:

var listCE = _context.Ce
  .Where(x => x.VuId == element.VuId)
  .Where(x => !boolparameter || x.Score == 8)
  .AsNoTracking()
  .ToList();

Which means if boolparameter is false, x.Score doesn't matter, since !false would equal to true and it satisfies OR condition. Likewise if boolparameter is true, then x.score will also be checked if it is equal to 8.

Or maybe with one Where condition:

var listCE = _context.Ce
  .Where(x => x.VuId == element.VuId && (!boolparameter || x.Score == 8))
  .AsNoTracking()
  .ToList();