Server Filter using Contains for Child List

[John]

I am trying to filter on a value in a child array of an object using server side filtering 

I have an object like:

public class person{
     public int id {get; set;}
 public List<int> accountIdList {get; set;}    <br>
}

On a grid I generate a custom filter template which allows a user to filter by Accounts (e.g a dropdown list of accounts).  
The datasourcerequest object on the server is populated with a filter.  I want to be able to intercept the filter and change the filter from an equals
to a contains

I've done the following

private DataSourceRequest InterceptRequest(DataSourceRequest request)
        {
            for (int idx = 0; idx < request.Filters; idx++)
            {
                var flt = filterList[idx] as FilterDescriptor;
                if (flt != null && flt.Member.ToString().Equals("accountIdList"))
                {
                    flt.Operator = FilterOperator.Contains;
                    flt.Value = 1;   //Hardcode as an example
                }
            }
        }

However when I call ToDataSourceResult I get an error stating an invalid cast from Int32 to IEnumerable<Int32>

I want to get a list of all persons who have an Account Id of 1.  How can I achieve this?

[Stefan]

Hello John,

If I understand correctly, the desired result is to change the filter operator from equals to contains? This can be achieved via custom binding:

http://docs.telerik.com/kendo-ui/aspnet-mvc/helpers/grid/binding/custom-binding

Please have in mind that the contains operator can filter only string values:

http://docs.telerik.com/kendo-ui/api/javascript/data/datasource#configuration-filter.operator

Additionally, if the end result is to get a list of all persons who have an Account Id of 1, the equals operator is better options than contains.

In order to assist you further, could please send a runnable example and provide additional information for the used scenario.

Regards,
Stefan
Telerik by Progress

[John]

Hi Stefan,

It is an integer that I will need to filter on.   The child array will be an array of integers.  For example accountIdList  may contain the values (1,2,3,4).  From the front end I would pass in a value of 1 so I need some way of checking if the value 1 is in the accountIdList.

Contains seemed the logical way for me but you have stated that this only works for strings so this won't work

[Stefan]

Hello John,

Thank you for the additional information.

I can confirm that this can be achieved only with custom binding. Please have in mind that in this case all of the operations like paging, filtering, sorting and grouping have to be implemented manually.

Let me know if you need additional information about the Kendo UI DataSource API.

Regards,
Stefan
Telerik by Progress