<script>
        function clickButton(selector) {
            var btn = document.querySelector(selector);
            if (btn && btn.click) {
                btn.click();
            }
        }
    </script>

@inject IJSRuntime _js

<style>
    /* hide the built-in button if you like */
    .myExcelExportButton {
        display:none;
    }
</style>

<button @onclick="@MyExternalExportTrigger">my external export button</button>

<TelerikGrid Data="@GridData" Pageable="true" Sortable="true" Resizable="true" Reorderable="true"
             FilterMode="@GridFilterMode.FilterRow" Groupable="true"
             Class="@GridClass">
    <GridToolBar>
        <GridCommandButton Class="@ExportBtnClass" Command="ExcelExport" Icon="@IconName.FileExcel">Export to Excel</GridCommandButton>
        <label><TelerikCheckBox @bind-Value="@ExportAllPages" />Export All Pages</label>
    </GridToolBar>
    <GridExport>
        <GridExcelExport FileName="telerik-grid-export" AllPages="@ExportAllPages" />
    </GridExport>

    <GridColumns>
        <GridColumn Field="@nameof(SampleData.ProductId)" Title="ID" Width="100px" />
        <GridColumn Field="@nameof(SampleData.ProductName)" Title="Product Name" Width="300px" />
        <GridColumn Field="@nameof(SampleData.UnitsInStock)" Title="In stock" Width="100px" />
        <GridColumn Field="@nameof(SampleData.Price)" Title="Unit Price" Width="200px" />
        <GridColumn Field="@nameof(SampleData.Discontinued)" Title="Discontinued" Width="100px" />
        <GridColumn Field="@nameof(SampleData.FirstReleaseDate)" Title="Release Date" Width="300px" />
    </GridColumns>
</TelerikGrid>

@code {
    // cascade through classes on the grid and/or on the built-in button to click it with JS
    // so that it can invoke the built-in export operations
    string GridClass { get; set; } = "MyGrid";
    string ExportBtnClass { get; set; } = "myExcelExportButton";
    async Task MyExternalExportTrigger()
    {
        var selector = $".{GridClass} .k-header .{ExportBtnClass}";
        await _js.InvokeVoidAsync("clickButton", selector);
    }



    List<SampleData> GridData { get; set; }
    bool ExportAllPages { get; set; }

    protected override void OnInitialized()
    {
        GridData = Enumerable.Range(1, 100).Select(x => new SampleData
        {
            ProductId = x,
            ProductName = $"Product {x}",
            UnitsInStock = x * 2,
            Price = 3.14159m * x,
            Discontinued = x % 4 == 0,
            FirstReleaseDate = DateTime.Now.AddDays(-x)
        }).ToList();
    }

    public class SampleData
    {
        public int ProductId { get; set; }
        public string ProductName { get; set; }
        public int UnitsInStock { get; set; }
        public decimal Price { get; set; }
        public bool Discontinued { get; set; }
        public DateTime FirstReleaseDate { get; set; }
    }
}

@page "/test"

<div>
    <TelerikGrid @ref="grid" Data="@GridData" @bind-Page="Page" PageSize="PageSize"
                 Pageable="true" Sortable="true" Groupable="true"
                 FilterMode="Telerik.Blazor.GridFilterMode.FilterMenu" 
                 ShowColumnMenu="true"
                 TotalCount="@TotalRowCount"
                 SelectionMode="GridSelectionMode.Single"
                 OnRead=@ReadData>
        <GridAggregates>
            <GridAggregate Field=@nameof(TestData.Name) Aggregate="@GridAggregateType.Count" />
            <GridAggregate Field=@nameof(TestData.Surname) Aggregate="@GridAggregateType.Count" />
            <GridAggregate Field=@nameof(TestData.Department) Aggregate="@GridAggregateType.Count" />
        </GridAggregates>
        <GridColumns>
            <GridColumn Field="@(nameof(TestData.Name))" FieldType="typeof(string)" Editable="false" Groupable="true" ShowColumnMenu="false" />
            <GridColumn Field="@(nameof(TestData.Surname))" FieldType="typeof(string)" Editable="false" Groupable="true" ShowColumnMenu="false" />
            <GridColumn Field="@(nameof(TestData.Department))" FieldType="typeof(string)" Editable="false" Groupable="true" ShowColumnMenu="false" />
            <GridCommandColumn Width="60px" Lockable="false" ShowColumnMenu="true">
                <GridCommandButton Command="View" Icon="information" ShowInEdit="false" OnClick="@ViewItem"></GridCommandButton>
            </GridCommandColumn>
        </GridColumns>
    </TelerikGrid>
</div>


@code {

    protected TelerikGrid<TestData> grid;
    protected List<TestData> GridData { get; set; }
    public int TotalRowCount { get; set; } = 0;
    public int Page { get; set; } = 1;
    public int PageSize { get; set; } = 10;

    protected async Task ReadData(GridReadEventArgs args)
    {
        await LoadData();
    }

    protected async Task LoadData()
    {
        GridData = await GetSampleData();
        TotalRowCount = 100;
    }

    protected async Task<List<TestData>> GetSampleData()
    {
        List<TestData> results = new List<TestData>();

        results.Add(new TestData { Name = "Name1", Surname = "Surname1", Department = "Department1" });
        results.Add(new TestData { Name = "Name2", Surname = "Surname2", Department = "Department1" });
        results.Add(new TestData { Name = "Name3", Surname = "Surname3", Department = "Department1" });
        results.Add(new TestData { Name = "Name4", Surname = "Surname4", Department = "Department1" });
        results.Add(new TestData { Name = "Name5", Surname = "Surname5", Department = "Department2" });
        results.Add(new TestData { Name = "Name6", Surname = "Surname6", Department = "Department2" });
        results.Add(new TestData { Name = "Name7", Surname = "Surname7", Department = "Department2" });
        results.Add(new TestData { Name = "Name8", Surname = "Surname8", Department = "Department3" });
        results.Add(new TestData { Name = "Name9", Surname = "Surname9", Department = "Department3" });
        results.Add(new TestData { Name = "Name10", Surname = "Surname10", Department = "Department4" });

        await Task.Delay(1000); //simulate loading delay ...

        return results;
    }

    protected void ViewItem(GridCommandEventArgs args)
    {
        //navigate to edit view ...
    }

    public class TestData
    {
        public string Name { get; set; }
        public string Surname { get; set; }
        public string Department { get; set; }
    }
}

<TelerikGrid Data=@GridData EditMode="@GridEditMode.Inline"
             Height="500px" AutoGenerateColumns="true" Pageable="true"
             OnDelete="@DeleteItem">
    <GridColumns>
        <GridAutoGeneratedColumns />

        <GridCommandColumn Width="100px">
            <GridCommandButton Command="Delete" Icon="delete" OnClick="@ConfirmDelete">Delete</GridCommandButton>
        </GridCommandColumn>

    </GridColumns>
</TelerikGrid>

@code {
    //for the confirmation - see the OnClick handler on the Delete button
    [CascadingParameter]
    public DialogFactory Dialogs { get; set; }

    async Task ConfirmDelete(GridCommandEventArgs e)
    {
        Product productToDelete = e.Item as Product;
        string confirmText = $"Are you sure you want to delete {productToDelete.Name}?";
        string confirmTitle = "Confirm Deletion!";
        //the actual confirmation itself
        bool userConfirmedDeletion = await Dialogs.ConfirmAsync(confirmText, confirmTitle);
        e.IsCancelled = !userConfirmedDeletion;//cancel the event if the user did not confirm
    }

    // only sample data operations follow

    public List<Product> GridData { get; set; }

    protected override async Task OnInitializedAsync()
    {
        GridData = Enumerable.Range(1, 50).Select(x => new Product { Id = x, Name = $"Name {x}" }).ToList();
    }

    private void DeleteItem(GridCommandEventArgs args)
    {
        Console.WriteLine("DELETING ITEM");
        var argsItem = args.Item as Product;

        GridData.Remove(argsItem);
    }

    public class Product
    {
        public int Id { get; set; }
        public string Name { get; set; }
    }
}