Hello Singh,

Thank you for the update and your sample. I have looked into and have found why you are having this issue. In your BindChildDetails method there are two changes to make. First is when you are creating the child grid layout you are using the GridModel and the GetGridModel for the parent where as instead you should use the following:

GridColumnLayoutModel grd = GetChildGridModel();

Then when you call GetData on grd you are passing in the path and layout when you already filtering the data from the datasource by the parent id. So you will either want stop pre-filtering it or instead call:

var res = grd.GetData();

So when you are doing the filtering yourself it would look like the following:

public JsonResult BindChildDetails(string path, string layout)
        {
            var pid = path.Substring(path.LastIndexOf(':') + 1);
            int parentId = int.Parse(pid);

            GridColumnLayoutModel grd = GetChildGridModel();

            var p = PopulateChild(parentId);
            grd.DataSource = p.AsQueryable();
            var res = grd.GetData();
            return res;
        }

 Thank you.

I have emailed you.

Thanks Mike

I have tried as you suggested but still getting the same error

--Model
public class ParentViewModel
{
  public int PId {get; set;}
  public string Name {get; set;}
  public ICollection<ChildViewModel> ChildDetails
}

Public class ChildViewModel
{
  public int CId {get; set;}
  public int PId {get; set;}
  public int CData {get; set;}
}

-- View
@model Infragistics.Web.Mvc.GridModel

(Html.Infragistics().Grid(Model))

--Controller

private GridModel GetGridModel()
{ 

            GridModel model = new GridModel();
            model.AutoGenerateColumns = false;
            model.AutoCommit = true;
            model.PrimaryKey = "PId";
            model.AutoGenerateLayouts = false;
            model.ID = "igGrid";

            model.LoadOnDemand = true;

            model.Columns.Add(new GridColumn { Key = "PId", Hidden = true, DataType = "number" });
            model.Columns.Add(new GridColumn { Key = "Name", HeaderText = "Parent Name ", DataType = "string" });
            model.DataSourceUrl = (Url.Action("BindParentDetails"));
          

            GridColumnLayoutModel childModel = GetChildGridModel();

            model.ColumnLayouts.Add(childModel);
            
            return model;
}

private GridModel GetChildGridModel()
{
            GridColumnLayoutModel childModel = new GridColumnLayoutModel();
            childModel.Key = "ChildDetails";
            childModel.PrimaryKey = "CID";
            childModel.ForeignKey = "PId";
            childModel.AutoGenerateColumns = false;
            childModel.Columns.Add(new GridColumn { Key = "CId", HeaderText = "Child ID", DataType = "number" });
            childModel.Columns.Add(new GridColumn { Key = "CData", HeaderText = "Child Data", DataType = "number" });
            childModel.DataSourceUrl = Url.Action("BindChildDetails");
            return childModel ;

}
        public JsonResult BindParentDetails()
        {
            GridModel rModel = GetGridModel();

            var p = _service.GetPDetails();

            rModel.DataSource = p.AsQueryable();
            var res = rModel.GetData();
            return res;
        }

        public JsonResult BindChildDetails(string path, string layout)
        {
            var pid = path.Substring(path.LastIndexOf(':') + 1);

            GridModel grd = GetGridModel();

            var p = _service.GetChildDetails(pId);
            grd.DataSource = p.AsQueryable();
            var res = grd.GetData(path, layout);
            return res;
        }