Components / Grid / Export

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Excel Export

You can export the grid to Excel with a click of a button. The current filter, sort, page, grouping, column order and column size are applied to the xlsx document.

When you click the Export button, your browser will receive the resulting file.

In This Article

Basics

To enable the Grid Excel Export, add a command button with the ExcelExport command name to the Grid toolbar.

<GridToolBarTemplate>
    <GridCommandButton Command="ExcelExport" Icon="@SvgIcon.FileExcel">Export to Excel</GridCommandButton>
</GridToolBarTemplate>

Optionally, you can also set the GridExcelExport tag settings under the GridExport tag to choose:

  • FileName - the name of the file. The grid will add the .xslx extension for you.
  • AllPages - whether to export the current page only, or the entire data from the data source.
  • Subscribe to Grid export events that allow further customizations of the exported columns or data.

Export the Grid to Excel - Example

@* You can sort, group, filter, page the grid, resize and reodrder its columns, and you can click the
    Export button to save the current data *@

<TelerikGrid Data="@GridData" Pageable="true" Sortable="true" Resizable="true" Reorderable="true"
             FilterMode="@GridFilterMode.FilterRow" Groupable="true" >

    <GridToolBarTemplate>
        <GridCommandButton Command="ExcelExport" Icon="@SvgIcon.FileExcel">Export to Excel</GridCommandButton>
        <label class="k-checkbox-label"><TelerikCheckBox @bind-Value="@ExportAllPages" />Export All Pages</label>
    </GridToolBarTemplate>

    <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 {
    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; }
    }
}

Programmatic Export

You can programmatically invoke the export feature of the Grid, by using the following methods exposed on the @ref of the Grid:

  • SaveAsExcelFileAsync - ValueTask - sends the exported excel file to the browser for download.
  • ExportToExcelAsync - Task<MemoryStream> - returns the exported data as a MemoryStream. The stream itself is finalized, so that the resource does not leak. To read and work with the stream, clone its available binary data to a new MemoryStream instance.

The same methods are exposed for exporting a CSV file.

Invoke the export function from code

@* Send the exported file for download and get the exported data as a memory stream *@

@using System.IO

<TelerikButton OnClick="@(async () => await GridRef.SaveAsExcelFileAsync())">Download the excel file</TelerikButton>
<TelerikButton OnClick="@GetTheDataAsAStream">Get the Exported Data as a MemoryStream</TelerikButton>

<TelerikGrid @ref="@GridRef"
             Data="@GridData"
             Pageable="true"
             Sortable="true"
             Resizable="true"
             Reorderable="true"
             FilterMode="@GridFilterMode.FilterRow"
             Groupable="true">

    <GridToolBarTemplate>
        <GridCommandButton Command="ExcelExport" Icon="@SvgIcon.FileExcel">Export to Excel</GridCommandButton>
        <label class="k-checkbox-label"><TelerikCheckBox @bind-Value="@ExportAllPages" />Export All Pages</label>
    </GridToolBarTemplate>

    <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 {
    private TelerikGrid<SampleData> GridRef { get; set; }

    private MemoryStream exportedExcelStream { get; set; }

    private async Task GetTheDataAsAStream()
    {
        MemoryStream finalizedStream = await GridRef.ExportToExcelAsync();

        exportedExcelStream = new MemoryStream(finalizedStream.ToArray());
    }

    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; }
    }
}

Customization

To customize the exported file, handle the OnBeforeExport or OnAfterExport events the Grid exposes.

The component allows you to control the data set that will be exported. It also provides built-in customization options for the columns such as Width, Title and more.

For more advanced customization (such as coloring the headers or bolding the titles) the Grid lets you get the MemoryStream of the file. Thus, you can customize it using the SpreadProcessing or the SpreadStreamProcessing libraries that are available with your license. Find examples on how to format the cells of the exported Excel file with RadSpreadProcessing and how to format the cells of the exported Excel file with RadSpreadStreamProcessing.

Read more about how to customize the exported file.

Notes

The Excel export has the following specifics:

  • Excel does not understand units different than px for the column Width, and if you use them (such as rem or %), it will fail to parse them and will render a collapsed (hidden) column with zero width.

  • Templates are not exported, because there is no provision in the framework for getting them at runtime. If a column, header or group header/footer has a template or aggregates, it will be ignored. The headers will be the Title of the column, the data is the data from the Field. If you need additional information, see if you can add it in a Field in the model, or create your own Excel file. Find a project example on how to generate your own exported file. Find additional information on how to export an image that is rendered in a Grid column template.

  • bool fields are exported as TRUE or FALSE strings, because there is no boolean data type in Excel and these string values are the most common ones used in data and macros.

  • Date and number formats are exported with the following format: mm/dd/yyyy hh:mm:ss plus the current app culture AM/PM specifier for dates, and Convert.ToDouble(value) for numbers (which uses the current thread culture). The Excel date formats are different than .NET date formats and Excel may not always recognize the column as dates, for example, if the entire date format from the .NET culture is used.

  • The Grid exports only <GridColumn> instances. Other types of columns are not exported, for example command, checkbox, hierarchy, group and row-drag columns.

  • If the Grid is using OnRead and is exporting all pages, it will fire an additional OnRead event at the time of exporting, with a request PageSize of 0. This will enable the component to obtain all data.

  • With Server-side Blazor, the file may become larger than the default SignalR connection limit, and this can disconnect the client and result in an error. Generally, this requires quite a lot of data to happen, but you may need to increase the size limit of the connection in the ConfigureServices method of your Startup.cs file, for example:

    C#

        services.AddServerSideBlazor().AddHubOptions(o =>
    {
        o.MaximumReceiveMessageSize = 1024 * 1024; // 1MB
    });

  • With Client-side Blazor (WebAssembly), all the code runs in the browser and, at the time of writing, is considerably slower than server-side Blazor, and it only has one actual thread. This means that while the file is being generated, the UI will be unresponsive, so you may want to show a loading sign to the user through the OnClick handler of the command button, something like:

    Component

    @* Exporting a lot of rows can be slow in a WebAssembly app more so than in a server-side app, and it blocks the UI *@

<TelerikGrid Data="@GridData" AutoGenerateColumns="true" Pageable="true">
    <GridToolBarTemplate>
        <GridCommandButton OnClick="@ShowLoadingSign" Command="ExcelExport" Icon="@SvgIcon.FileExcel">Export to Excel</GridCommandButton>
        <GridCommandButton OnClick="@ShowLoadingSign" Command="CsvExport" Icon="@SvgIcon.FileCsv">Export to CSV</GridCommandButton>
    </GridToolBarTemplate>
    <GridExport>
        <GridExcelExport AllPages="true" FileName="telerik-grid-export" />
        <GridCsvExport AllPages="true" FileName="telerik-grid-export" />
    </GridExport>
</TelerikGrid>

<TelerikWindow Visible="@isExporting" Modal="true">
    <WindowTitle>Please wait...</WindowTitle>
    <WindowContent>We are exporting your data, your file will download shortly.</WindowContent>
</TelerikWindow>

@code {
    bool isExporting { get; set; }

    async Task ShowLoadingSign()
    {
        isExporting = true;
        StateHasChanged();
        // This won't work for server-side Blazor, the UI will render immediately after the delay and the loading sign will only flicker
        await Task.Delay(50);
        isExporting = false;
    }

    List<SampleData> GridData { get; set; }

    protected override void OnInitialized()
    {
        GridData = Enumerable.Range(1, 1000).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; }
    }
}

See Also

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