CODEWITHSUNDEEP
c#entity-framework
Sinan Chik
Sinan Chik

Reputation: 81

Entity Framework add parameter

In my application (Winforms), there is 'Search' form. And I have 9 fields (such as name, surname, city etc.) I need, if 4 fields are filled, I will search by 4 fields.

For example: user entered; Name, Surname, City

Application will search by those fields.

With SqlConnection, I am using parameters.Add method. But with Entity Framework, I don't know how can I use it.

Sorry for my english :)

Thanks

Upvotes: 0

Views: 416

Answers (1)

Felipe Oriani
Felipe Oriani

Reputation: 38608

You could check in your method if the parameters is empty and if not, add the parameter as a condition using the Where method. You just execute the query when you call a method to concrete it in a type, for sample: FirstOrDefault, ToList(), so you can prepare you query adding the parameters. You could try something like this:

// create the query type (IQueryable, DbSet, etc...)
IQueryable<Entity> query = context.Entity;

// check the parameters and add using the Where method
if (!string.IsNullOrEmpty(userName))
   query = query.Where(x => x.UserName.Constains(userName));

if (!string.IsNullOrEmpty(surName))
   query = query.Where(x => x.SurName.Constains(surName));

if (!string.IsNullOrEmpty(city))
   query = query.Where(x => x.City == city);

// execute the query and get results...
var result = query.ToList();

Upvotes: 3

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