Use String Value as a Variable Name in C#

Question

I have a string that is being passed to my controller in Razor Pages. This string contains the name of one of 8 possible Booleans as selected by the user. I am attempting to use this Boolean Name in a SQL server query as shown below.

try
{
     var test = await _context.GuestModel
     .Include(r => r.PatientModel)
     .OrderByDescending(r => r.GuestLastName)
     .Where(r => r.booleanName  == true)
     .ToListAsync();
     return test;
}

booleanName is the string containing the Boolean Name I need to use, but so far I have not been able to access that information successfully.

You can't just do that in a straightforward manner. You'll either have to build up the expression tree yourself using reflection, or use a library such as [DynamicLinq](https://dynamic-linq.net/) to do that for you. — Kirk Woll, Jun 07 '22 at 14:02
At some point, you are going to have to translate what the Razor page calls the property and what the database calls the field. They shouldn't (have to) be the same. — Neil, Jun 07 '22 at 14:02

score 0 · Answer 1 · answered Jun 07 '22 at 14:02

0

Use a switch or if/else blocks to pick from one of eight possible versions of the query based on the string.

answered Jun 07 '22 at 14:02

Joel Coehoorn

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Yeah I am leaning this way, and it will definitely work. Was just interested to learn if there was a cleaner way. – WreckingCrew Jun 07 '22 at 14:24
@WreckingCrew `Dictionary` might look cleaner. – Joel Coehoorn Jun 07 '22 at 14:28

Use String Value as a Variable Name in C#

1 Answers1