Error in Entity framework query (Missing cast)

Question

public List<ProjectImpacts> getProjectImpactsByProjeactIDAndImpactName(String prefe , String impcName)
{ 
    String xim =  cecbContext.Impacts.First(i=>i.impt_name.Contains(impcName)).impt_reference;

    IQueryable<ProjectImpacts> query = from c in cecbContext.ProjectImpacts
            join b in cecbContext.Impacts on c.impt_reference equals b.impt_reference             
            where c.proj_reference == prefe && c.impt_reference == xim
            select b.impt_name;

    List<ProjectImpacts> SelectedImpacts = query.ToList(); //query.Select(refe => new ProjectImpacts { impt_reference =   }).ToList();

    return SelectedImpacts;
}

I'm getting an error in this query:

Cannot implicitly convert type 'System.Linq.IQueryable' to 'System.Linq.IQueryable'. An explicit conversion exists (are you missing a cast?)

Sergey Kalinichenko · Accepted Answer · 2013-04-06 02:44:02Z

3

This is because your query selects a name at the end:

IQueryable<ProjectImpacts> query = from c in cecbContext.ProjectImpacts
    join b in cecbContext.Impacts on c.impt_reference equals b.impt_reference             
    where c.proj_reference == prefe && c.impt_reference == xim
    // select b.impt_name; // <<== Replace this...
    select c;              // <<== with this.

The type parameter T of the generic IQueryable<T> corresponds to the type of the object selected in the query. Since you select a name (which is presumably a string), you got an IQueriable<string>. Once you select c, which is ProjectImpacts, you'd get IQueryable<ProjectImpacts> as your result

edited Apr 6, 2013 at 2:44

answered Apr 6, 2013 at 2:11

Sergey Kalinichenko

729k85 gold badges1.2k silver badges1.6k bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Sergey Kalinichenko Over a year ago

@Gayashan It looks like ProjectImpacts is c, not b; b is Impacts. Try the changed query and see if it helps.

Collectives™ on Stack Overflow

Error in Entity framework query (Missing cast)

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related