How to return LINQ object from method?

Question

How to return LINQ object from method?

c# entity-framework linq

Question

I have method which has LINQ query and query return columns from multiple tables.

How can I return that LINQ results object and catch it in caller method iterate results and assign to model class?

public ??? GetLocation(string CustomerNum)
    {
        if (!string.IsNullOrEmpty(CustomerNum))
        {
            var results = from ca in _context.CUS_ADDRESS
                           join cad in _context.CUS_ADDRESS_DETAIL on ca.CUS_ADDRESS_ID equals cad.CUS_ADDRESS_ID
                          where (cad.PRIORITY_SEQ == 0) && (ca.MASTER_CUSTOMER_ID == CustomerNum)
                           select new
                           {
                               CustomerNumber = ca.MASTER_CUSTOMER_ID,
                               ca.ADDRESS_1,
                               ca.ADDRESS_2,
                               ca.ADDRESS_3,
                               ca.ADDRESS_4,
                               ca.CITY,
                               ca.STATE,
                               ca.COUNTRY_DESCR,
                               cad.ADDRESS_TYPE_CODE,
                               cad.ADDRESS_STATUS_CODE
                           };
            return results;
        }
        else
        {
            return null;
        }
    }

Caller method

var results = Data.GetLocation(CustomerNum)
if (results.Any())
{
   var location = results.FirstOrDefault();
   .....
   .....
 }

What will be the GetLocation return type?

James123

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Habib · Accepted Answer · 5/23/2017 12:33:29 PM

You are creating an anonymous object with select new, you can't return a collection of anonymous object from your function, instead you have to create a class which would have all the properties from your select statement and then return IQueryable<YourClass>

class YourClass
{
    public int CustomerNumber { get; set; }
    public string ADDRESS_1 { get; set; }
    //..............
}

and then :

var results = from ca in _context.CUS_ADDRESS
                           join cad in _context.CUS_ADDRESS_DETAIL on ca.CUS_ADDRESS_ID equals cad.CUS_ADDRESS_ID
                          where (cad.PRIORITY_SEQ == 0) && (ca.MASTER_CUSTOMER_ID == CustomerNum)
                           select new YourClass
                           {
                               CustomerNumber = ca.MASTER_CUSTOMER_ID,
                               ADDRESS_1 = ca.ADDRESS_1,
                               //...............

And modify your function return type as:

public IQueryable<YourClass> GetLocation(string CustomerNum)

You can look at this question for returning IQueryable or Not

How to return LINQ object from method?

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