On initialization of the Grid the oDataString is correct, but when I apply a Filter (through the FilterMenu) or apply a sort to a Grid column the ToODataString extension method throws with null reference exception. If the FilterMode is set to FilterRow or revert back to 2.16.0 everything works as expected. 

<AdminEdit>

This bug extends to the functionality of the FilterMenu as a feature and is not connected only to the ToODataString();

</AdminEdit>

It will be useful if the grid column state contains the Field parameter if such is specified.

This will make easier mapping the ColumnState entity to the actual column.

I am using EF on my backend and when I group I get an error like this one:

Unhandled exception rendering component: Processing of the LINQ expression '(GroupByShaperExpression:
      KeySelector: (t.FirstName), 
      ElementSelector:(EntityShaperExpression: 
          EntityType: Customer
          ValueBufferExpression: 
              (ProjectionBindingExpression: EmptyProjectionMember)
          IsNullable: False
      )
      )' by 'RelationalProjectionBindingExpressionVisitor' failed. This may indicate either a bug or a limitation in EF Core. See https://go.microsoft.com/fwlink/?linkid=2101433 for more detailed information.
System.InvalidOperationException: Processing of the LINQ expression '(GroupByShaperExpression:
KeySelector: (t.FirstName), 
ElementSelector:(EntityShaperExpression: 
    EntityType: Customer
    ValueBufferExpression: 
        (ProjectionBindingExpression: EmptyProjectionMember)
    IsNullable: False
)
)' by 'RelationalProjectionBindingExpressionVisitor' failed. This may indicate either a bug or a limitation in EF Core. See https://go.microsoft.com/fwlink/?linkid=2101433 for more detailed information.
   at Microsoft.EntityFrameworkCore.Query.Internal.RelationalProjectionBindingExpressionVisitor.VisitExtension(Expression extensionExpression)
   at System.Linq.Expressions.Expression.Accept(ExpressionVisitor visitor)

and a lot more line through the EF Core expression classes.

-----

ADMIN EDIT

    protected override void OnInitialized()
    {
        GridData = ProductService.GetProducts().ToList();
    }

----

I want to customize the appearance of the header of a certain column, and a bit of CSS backgrounds could help, but I can't do this with the HeaderTemplate alone, nor with content in it because of the padding the cells have.

So, I would like the ability to set the CSS class of the header cell of the column.

At the moment, the CollapsedGroups  collection in the grid state is the indexes of the root-level groups that you can collapse. I want to also be able to control the expanded state of nested groups.

ADMIN EDIT:

Ideas I can see are the following, do add your vote and comments on how you expect that to be exposed:

• a form of Id/field in the group descriptor that controls this. Caveat - groups don't generally have such an id and the descriptor does not control the UI, it controls the data.
• an event that provides the level, field name and group value that lets me choose this for every group as it renders. Caveat - might not plug in the state, but if you have a certain business logic for that you can just keep it in that event always, regardless of the grid state, or keep additional information in an application state.
• the current indexes could become recursive (see the image attached below). Caveat: you can't be sure that the next time data loads the data and so the groups will be the same when loading state

it would be helpful to have the ability to set Class attribute for rendered TD.

this would allow for example to set a background color for a column

For example, when I have two levels of grouping, I want to render only the inner footer templates, but not the outer.

While this is possible with some CSS like the snippet below, this does not scale well, and does not work well for arbitrary number of groups

<style>
    .k-group-footer + .k-group-footer {
       display:none;
    }
</style>

Group by the Vacation and Team columns to see the effect

<TelerikGrid Data=@GridData Groupable="true" Pageable="true">
    <GridColumns>
        <GridColumn Field=@nameof(Employee.Name) Groupable="false" />
        <GridColumn Field=@nameof(Employee.Team) Title="Team">
            <GroupFooterTemplate>
                Team group footer
            </GroupFooterTemplate>
        </GridColumn>
        <GridColumn Field=@nameof(Employee.IsOnLeave) Title="On Vacation">
            <GroupFooterTemplate>
                IsOnLeave group footer
            </GroupFooterTemplate>
            </GridColumn>
    </GridColumns>
</TelerikGrid>

@code {
    public List<Employee> GridData { get; set; }

    protected override void OnInitialized()
    {
        GridData = new List<Employee>();
        var rand = new Random();
        for (int i = 0; i < 15; i++)
        {
            GridData.Add(new Employee()
            {
                EmployeeId = i,
                Name = "Employee " + i.ToString(),
                Team = "Team " + i % 3,
                IsOnLeave = i % 2 == 0
            });
        }
    }

    public class Employee
    {
        public int EmployeeId { get; set; }
        public string Name { get; set; }
        public string Team { get; set; }
        public bool IsOnLeave { get; set; }
    }
}

If I add an await-ed call in the OnRowClick handler, then I cannot alter the grid state later in the code. It only works if the method is called again (e.g., a second click on the same row).

<AdminEdit>

This affects other Grid events too, for example, the PageChanged

</AdminEdit>

A workaround is to use synchronous code (remove the await call):

@inject IJSRuntime JsInterop

<TelerikGrid Data="@salesTeamMembers" OnRowClick="@OnRowClickHandler" @ref="@GridRef">
    <DetailTemplate>
        @{
            var employee = context as MainModel;
            <TelerikGrid Data="employee.Orders" Pageable="true" PageSize="5">
                <GridColumns>
                    <GridColumn Field="OrderId"></GridColumn>
                    <GridColumn Field="DealSize"></GridColumn>
                </GridColumns>
            </TelerikGrid>
        }
    </DetailTemplate>
    <GridColumns>
        <GridColumn Field="Id"></GridColumn>
        <GridColumn Field="Name"></GridColumn>
    </GridColumns>
</TelerikGrid>

@code {
    List<MainModel> salesTeamMembers { get; set; }
    TelerikGrid<MainModel> GridRef { get; set; }

    async Task OnRowClickHandler(GridRowClickEventArgs args) {
        // After adding this line, it now requires a double click when the InvokeAsync call uses "await"
         var width = JsInterop.InvokeAsync<int>("getWidth");


        var model = args.Item as MainModel;
        int index = salesTeamMembers.IndexOf(model);
        //todo: you may want to take paging into account for example, or use js interop to get the index of the row based on contents from it like id
        if (index > -1) {
            var state = GridRef.GetState();
            state.ExpandedRows = new List<int> { index };

            await GridRef.SetState(state);
        }

    }


    protected override void OnInitialized() {
        salesTeamMembers = GenerateData();
    }

    private List<MainModel> GenerateData() {
        List<MainModel> data = new List<MainModel>();
        for (int i = 0; i < 5; i++) {
            MainModel mdl = new MainModel { Id = i, Name = $"Name {i}" };
            mdl.Orders = Enumerable.Range(1, 15).Select(x => new DetailsModel { OrderId = x, DealSize = x ^ i }).ToList();
            data.Add(mdl);
        }
        return data;
    }

    public class MainModel {
        public int Id { get; set; }
        public string Name { get; set; }
        public List<DetailsModel> Orders { get; set; }
    }

    public class DetailsModel {
        public int OrderId { get; set; }
        public double DealSize { get; set; }
    }
}

Sample reproducible with workaround (to initialize the data source so it is not null) is below

Sample error and stack trace

<TelerikGrid Data=@GridData Pageable="true" Height="300px">
    <GridColumns>
        <GridColumn Field="@(nameof(Employee.EmployeeId))">
            <FooterTemplate>
                some footer
            </FooterTemplate>
        </GridColumn>
        <GridColumn Field=@nameof(Employee.Salary) Title="Salary">
        </GridColumn>
        <GridColumn Field=@nameof(Employee.Name)>
        </GridColumn>
    </GridColumns>
</TelerikGrid>

@code {
    public List<Employee> GridData { get; set; } // = new List<Employee>(); // workaround

    public class Employee
    {
        public int EmployeeId { get; set; }
        public string Name { get; set; }
        public decimal Salary { get; set; }
    }
}

I want to edit the Excel file the grid exports before it gets to the user. For example, to add a sheet with data I want to generate, or to change columns, formats, colors.

----

ADMIN EDIT

I have attached to this post an example that shows how you can generate your own exported file so you can customize colors, sheets and so on. It also shows how to cache the DataSourceRequest of the grid so you can extract only the current page or all data, and so you can also apply the current grid sorts/filters and so on to the export. This also lets you add metadata to the sheet such as the current user settings such as filters that resulted in this filter.

----

I want to be able to enter numbers and the grid to filter numeric fields too according to those numbers. Enums would be nice too.

**Admin Edit**

The feature request will be researched and evaluated. It contradicts to our datasource filtering logic that relies on the type of the fields. Thus, it is highly possible that we will handle the task through a knowledge base example.

**Admin Edit**

Please add a feature to export the grid to Microsoft Word file

---

ADMIN EDIT:

I am attaching a sample to this post that you can use to generate the docx file through the Telerik Document Processing libraries by looping over the data.

You can extend it further (add more fields, refactor so it is more reusable, extract to service,...) and if you would like to export the current grid data, see about implementing the data operations manually through the OnRead event - you can cache the DataSourceRequest object and then run a .ToDataSourceResult() query on the data to get what the grid displays on its current page. An example of a similar approach is available here for a customized excel export.

You can also read more about working with tables in a Word document here to apply more styling options as needed.

---

Hello,

When using grid command button edit with the onedit handler shown in this documentation https://docs.telerik.com/blazor-ui/components/grid/editing/inline

There is a bug that causes the grid to reset to the first page when editing the last item on any page that isn't the first. In other words we can edit the last item in the gird on the first page but not on the second, third, fourth...etc. 
I have taken out all the logic in my edit handler as well and the problem still presents itself. 

Below is the relevenat code sample and I have also zipped a short video demonstrating the behavior.

<TelerikGrid @ref="@GridNameHere"
                             Class="smallerFont"
                             Data="@DataHere"
                             Pageable="true"
                             Page="@Page"
                             PageSize="@PageSize"
                             TotalCount="@Total"
                             Sortable="@true"
                             Groupable="@false"
                             FilterMode="@GridFilterMode.FilterMenu"
                             Reorderable="@true"
                             OnEdit="@OnEdit"
                             OnUpdate="@OnUpdate"
                             OnCreate="@OnUpdate">
                    <GridToolBar>
                        <GridCommandButton Command="Add" Icon="add">Add</GridCommandButton>
                    </GridToolBar>
                    <GridColumns>
                        <GridCommandColumn Width="150px">
                            <GridCommandButton Command="Edit" Icon="edit">Edit</GridCommandButton>
                            <GridCommandButton Command="Save" Icon="save" ShowInEdit="true">Save</GridCommandButton>
                            <GridCommandButton Command="Cancel" Icon="cancel" ShowInEdit="true">Cancel</GridCommandButton>
                        </GridCommandColumn>

                        <GridColumn Field="@(nameof(ModelName.FieldName))" Title="Column Name" Width="100px" />

                    </GridColumns>
                </TelerikGrid>

//Handler for edit

 protected void OnEdit(GridCommandEventArgs args)
{

// no code in here and problem still presents itself but feel free to put anything I recommend using the sample from the documentation above

}