CODEWITHSUNDEEP
asp.net-mvcentity-framework-core
Jake
Jake

Reputation: 604

how to use LINQ to filter items in ViewData[ " " ] = new SelectList()?

I have a model that looks like this:

public partial class ProgramType
{
    public int PgmId { get; set; }
    public string PgmDescr { get; set; }
    public string PgmDescrLong { get; set; }

    public virtual ICollection<NewProgram> NewProgram { get; set; }
    public virtual ICollection<NewForm> NewForm { get; set; }        
}

Which is populated with this data:

+-------+----------+--------------+
| PgmId | PgmDescr | PgmDescrLong |
+-------+----------+--------------+
| 1     | CERT     | Certificate  |
+-------+----------+--------------+
| 2     | DEG      | Degree       |
+-------+----------+--------------+
| 3     | DIP      | Diploma      |
+-------+----------+--------------+

Using EF Core, I have scaffolded a Controller for the NewProgram model. The Create() action defines the Value/Text fields of a dropdown list which displays items from the ProgramType table:

ViewData["ProgramType"] = new SelectList(_context.ProgramType, "PgmId", "PgmDescrLong");

But I want to limit the dropdown list to particular values depending on which Controller I'm working on. I can get this to limit the dropdown list to display only "Certificate":

ViewData["ProgramType"] = new SelectList(_context.ProgramType, "PgmId", "PgmDescrLong").Where(x => x.Text.Contains("Certificate"));

But I want it to show both "Certificate" and "Diploma". This does not work:

ViewData["ProgramType"] = new SelectList(_context.ProgramType, "PgmId", "PgmDescrLong").Where(x => x.Text.Contains("Certificate", "Diploma"));

How can I accomplish this?

Upvotes: 1

Views: 1021

Answers (1)

Willy David Jr
Willy David Jr

Reputation: 9171

Try this:

string[] strArray = new string[] { "Certificate", "Diploma" };
ViewData["ProgramType"] = new SelectList(db.Programs, "PgmId", "PgmDescrLong").Where(x => strArray.Any(y => y == x.Text));

What you do is that create an array of string that you want to show on your dropdownlist.

From there, we will use that array to create a query that is like a SQL IN operator query just like this one:

Where(x => strArray.Any(y => y == x.Text));

Upvotes: 1

Related Questions