'IEnumerable' does not contain a definition for 'ToDataSourceResult'

[Radek]

Hello,

I created new project using Telerik wizard. I am trying to populate a grid with data-source using ajax but I am failing at using ToDataSourceResult. I am getting error 

'IEnumerable<Person>' does not contain a definition for 'ToDataSourceResult' and the best extension method overload 'QueryableExtensions.ToDataSourceResult(DataTable, DataSourceRequest)' requires a receiver of type 'System.Data.DataTable'

I compared it with project created by Telerik wizard for page with grid and still don't see why this error occurs.

Please see attached figure. It is screenshot taken from HomeController where I am trying to get data-source from IEnumerable. 

[Radek]

I found the problem, it was definition of request which was of type string and not DataSourceRequest.

Fixed version of method:

public IActionResult GetPeople([DataSourceRequest] DataSourceRequest request)
{
    IEnumerable<Person> result = Enumerable.Range(0, 50).Select(i => new Person
    {
        Id = i,
        Name = i.ToString(),
        Description = i.ToString(),
        Age = i
    });
    var dsResult = result.ToDataSourceResult(request);
    return Json(dsResult);
}