GridPersistentLayout Class

Contains information about a DxGrid‘s layout.

Namespace: DevExpress.Blazor

Assembly: DevExpress.Blazor.v23.2.dll

NuGet Package: DevExpress.Blazor

Declaration

public class GridPersistentLayout :
    IEquatable<GridPersistentLayout>

Related API Members

The following members return GridPersistentLayout objects:

• DxGrid.SaveLayout()
• GridPersistentLayoutEventArgs.Layout
• IGrid.SaveLayout()

Remarks

The Grid allows you to save and restore its layout settings that a user can change in the UI. A saved layout object includes the following data:

Saved information	Grid parameter	GridPersistentLayout’s property
The current page.	DxGrid.PageIndex	Layout.PageIndex
The maximum number of rows displayed on a page.	DxGrid.PageSize	Layout.PageSize
A Boolean value that indicates whether the Grid displays all rows on one page.	DxGrid.ShowAllRows	Layout.ShowAllRows
Search text.	DxGrid.SearchText	Layout.SearchText
Filter values.	A concatenation of all Grid column filter criteria[1] with the AND operator.	Layout.FilterCriteria
Settings for individual columns. See the table below.		Layout.Columns.Item(i)

Important

DevExpress components can incorrectly serialize custom enumeration values in criteria operators. Refer to the following troubleshooting topic for more information: The XXX enumeration type is not registered for the parse operation…

The GridPersistentLayout.Columns collection stores information about column layout settings. Each collection item (a GridPersistentLayoutColumn object) includes the following data:

Saved information	Grid column parameter	GridPersistentLayoutColumn’s property
Column type	A column type defined in the markup: data, command, or selection.	LayoutColumn.ColumnType
A data field name	DxGridColumn.FieldName	LayoutColumn.FieldName
Group index[2]	DxGridColumn.GroupIndex	LayoutColumn.GroupIndex
Sort index	DxGridColumn.SortIndex	LayoutColumn.SortIndex
Sort direction	DxGridColumn.SortOrder	LayoutColumn.SortOrder
Position	DxGridColumn.VisibleIndex	LayoutColumn.VisibleIndex
Visibility	DxGridColumn.Visible	LayoutColumn.Visible
Width	DxGridColumn.Width	LayoutColumn.Width

Keep the Layout Persistence

To save and restore the Grid layout automatically, handle the following events:

• LayoutAutoSaving – Fires each time the grid’s layout changes and allows you to save the layout.
• LayoutAutoLoading – Fires once the grid component is initialized and allows you to restore the saved layout.

The code below demonstrates how to ensure the grid’s layout persistence. When the component layout changes, the LayoutAutoSaving event handler saves the updated layout to the browser’s local storage. Once the page is reloaded or restored, the LayoutAutoLoading event handler loads the most recently-saved layout from the local storage and applies it to the grid.

Razor

@using System.Text.Json
@inject NwindDataService NwindDataService
@inject IJSRuntime JSRuntime

@if(PreRendered) {
    <DxGrid @ref="Grid" Data="@GridData" AutoExpandAllGroupRows="true"
        ColumnResizeMode="GridColumnResizeMode.NextColumn"
        ShowGroupPanel="true" ShowFilterRow="true"
        PageSizeSelectorVisible="true" PageSizeSelectorAllRowsItemVisible="true"
        LayoutAutoLoading="Grid_LayoutAutoLoading"
        LayoutAutoSaving="Grid_LayoutAutoSaving">
        <Columns>
            <DxGridDataColumn FieldName="Country" GroupIndex="0" />
            <DxGridDataColumn FieldName="City" GroupIndex="1" />
            <DxGridDataColumn FieldName="CompanyName" />
            <DxGridDataColumn FieldName="Address" />
            <DxGridDataColumn FieldName="Phone" />
            <DxGridDataColumn FieldName="ContactName" />
        </Columns>
    </DxGrid>
} else {
    <em>Loading...</em>
}

@code {
    const string LocalStorageKey = "Grid-LayoutPersistence-Data";

    bool PreRendered { get; set; }
    IGrid Grid { get; set; }
    object GridData { get; set; }

    protected override async Task OnInitializedAsync() {
        GridData = await NwindDataService.GetCustomersAsync();
    }

    protected override void OnAfterRender(bool firstRender) {
        if(firstRender) {
            PreRendered = true;
            StateHasChanged();
        }
    }

    async Task Grid_LayoutAutoLoading(GridPersistentLayoutEventArgs e) {
        e.Layout = await LoadLayoutFromLocalStorageAsync();
    }

    async Task Grid_LayoutAutoSaving(GridPersistentLayoutEventArgs e) {
        await SaveLayoutToLocalStorageAsync(e.Layout);
    }

    async Task<GridPersistentLayout> LoadLayoutFromLocalStorageAsync() {
        try {
            var json = await JSRuntime.InvokeAsync<string>("localStorage.getItem", LocalStorageKey);
            return JsonSerializer.Deserialize<GridPersistentLayout>(json);
        } catch {
            // Mute exceptions for the server prerender stage
            return null;
        }
    }

    async Task SaveLayoutToLocalStorageAsync(GridPersistentLayout layout) {
        try {
            var json = JsonSerializer.Serialize(layout);
            await JSRuntime.InvokeVoidAsync("localStorage.setItem", LocalStorageKey, json);
        } catch {
            // Mute exceptions for the server prerender stage
        }
    }
}

Invoice

using System;
using System.Collections.Generic;
using System.Runtime.InteropServices;

namespace BlazorDemo.Data.Northwind {
    public class Invoice {
        public string ShipName { get; set; }
        public string ShipAddress { get; set; }
        public string ShipCity { get; set; }
        public string ShipRegion { get; set; }
        public string ShipPostalCode { get; set; }
        public string ShipCountry { get; set; }
        public string CustomerId { get; set; }
        public string CustomerName { get; set; }
        public string Address { get; set; }
        public string City { get; set; }
        public string Region { get; set; }
        public string PostalCode { get; set; }
        public string Country { get; set; }
        public string Salesperson { get; set; }
        public int OrderId { get; set; }
        public DateTime? OrderDate { get; set; }
        public DateTime? RequiredDate { get; set; }
        public DateTime? ShippedDate { get; set; }
        public string ShipperName { get; set; }
        public int ProductId { get; set; }
        public string ProductName { get; set; }
        public decimal UnitPrice { get; set; }
        public short Quantity { get; set; }
        public float Discount { get; set; }
        public decimal? ExtendedPrice { get; set; }
        public decimal? Freight { get; set; }
    }
}

Customer

using System;
using System.Collections.Generic;
using System.Runtime.InteropServices;

namespace BlazorDemo.Data.Northwind {
    public partial class Customer {
        public Customer() {
            Orders = new HashSet<Order>();
        }

        public string CustomerId { get; set; }
        public string CompanyName { get; set; }
        public string ContactName { get; set; }
        public string ContactTitle { get; set; }
        public string Address { get; set; }
        public string City { get; set; }
        public string Region { get; set; }
        public string PostalCode { get; set; }
        public string Country { get; set; }
        public string Phone { get; set; }
        public string Fax { get; set; }

        public virtual ICollection<Order> Orders { get; set; }
    }
}

NwindDataService.Invoices

using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using BlazorDemo.Data.Northwind;
using BlazorDemo.DataProviders;

namespace BlazorDemo.Services {
    public partial class NwindDataService {
        public Task<IEnumerable<Invoice>> GetInvoicesAsync(CancellationToken ct = default) {
            // Return your data here
        }
    }
}

NwindDataService.Customers

using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using BlazorDemo.Data.Northwind;
using BlazorDemo.DataProviders;

namespace BlazorDemo.Services {
    public partial class NwindDataService {
        public Task<IEnumerable<Customer>> GetCustomersAsync(CancellationToken ct = default) {
            // Return your data here
        }
    }
}

Program.cs

// ...
builder.Services.AddScoped<NwindDataService>();

Run Demo: Save and Restore the Layout

Prevent Saving a Setting

To prevent a specific grid setting from saving to GridPersistentLayout object, clear the corresponding option before save the grid layout. The code sample below demonstrates how to remove information about search text, filter, and grouping from the layout settings to be saved.

async Task Grid_LayoutAutoSaving(GridPersistentLayoutEventArgs e) {
    var layout = e.Layout with { 
        // Prevent saving a search string text to the client layout
        SearchText = null,
        // Prevent saving a filter to the client layout
        FilterCriteria = null,
        // Prevent saving group settings to the client layout
        Columns = new GridPersistentLayoutCollection<GridPersistentLayoutColumn>(
            e.Layout.Columns.Select(i => i with { GroupIndex = -1 })
        )
    };
    await SaveLayoutToLocalStorageAsync(layout);
}

Save and Restore the Layout on Demand

To save and restore the Grid layout when necessary (for example, on a button click), call the following methods:

• SaveLayout() – Saves information about a Grid’s layout.
• LoadLayout(GridPersistentLayout) – Loads a layout and applies it to the Grid.

The code below displays two buttons: Save Layout and Load Layout. When a user clicks the first button, the current Grid layout is saved to the Layout parameter. Once a user clicks the second button, the component loads the most recently-saved layout from the Layout parameter and applies it to the grid.

Razor

@using System.Text.Json
@inject NwindDataService NwindDataService
@inject IJSRuntime JSRuntime

<DxButton Text="Save Layout" Click="OnSaveClick" />
<DxButton Text="Load Layout" Click="OnLoadClick" />

<DxGrid @ref="Grid" 
        Data="@GridData" 
        AutoExpandAllGroupRows="true"
        ColumnResizeMode="GridColumnResizeMode.NextColumn"
        ShowGroupPanel="true" 
        ShowFilterRow="true"
        PageSizeSelectorVisible="true" 
        PageSizeSelectorAllRowsItemVisible="true">
    <Columns>
        <DxGridDataColumn FieldName="Country" GroupIndex="0" />
        <DxGridDataColumn FieldName="City" GroupIndex="1" />
        <DxGridDataColumn FieldName="CompanyName" />
        <DxGridDataColumn FieldName="Address" />
        <DxGridDataColumn FieldName="Phone" />
        <DxGridDataColumn FieldName="ContactName" />
    </Columns>
</DxGrid>

@code {
    IGrid Grid { get; set; }
    object GridData { get; set; }
    GridPersistentLayout Layout { get; set; }

    protected override async Task OnInitializedAsync() {
        GridData = await NwindDataService.GetCustomersAsync();
    }

    void OnSaveClick() {
        Layout = Grid.SaveLayout();
    }

    void OnLoadClick() {
        Grid.LoadLayout(Layout);
    }
}

Invoice

using System;
using System.Collections.Generic;
using System.Runtime.InteropServices;

namespace BlazorDemo.Data.Northwind {
    public class Invoice {
        public string ShipName { get; set; }
        public string ShipAddress { get; set; }
        public string ShipCity { get; set; }
        public string ShipRegion { get; set; }
        public string ShipPostalCode { get; set; }
        public string ShipCountry { get; set; }
        public string CustomerId { get; set; }
        public string CustomerName { get; set; }
        public string Address { get; set; }
        public string City { get; set; }
        public string Region { get; set; }
        public string PostalCode { get; set; }
        public string Country { get; set; }
        public string Salesperson { get; set; }
        public int OrderId { get; set; }
        public DateTime? OrderDate { get; set; }
        public DateTime? RequiredDate { get; set; }
        public DateTime? ShippedDate { get; set; }
        public string ShipperName { get; set; }
        public int ProductId { get; set; }
        public string ProductName { get; set; }
        public decimal UnitPrice { get; set; }
        public short Quantity { get; set; }
        public float Discount { get; set; }
        public decimal? ExtendedPrice { get; set; }
        public decimal? Freight { get; set; }
    }
}

Customer

using System;
using System.Collections.Generic;
using System.Runtime.InteropServices;

namespace BlazorDemo.Data.Northwind {
    public partial class Customer {
        public Customer() {
            Orders = new HashSet<Order>();
        }

        public string CustomerId { get; set; }
        public string CompanyName { get; set; }
        public string ContactName { get; set; }
        public string ContactTitle { get; set; }
        public string Address { get; set; }
        public string City { get; set; }
        public string Region { get; set; }
        public string PostalCode { get; set; }
        public string Country { get; set; }
        public string Phone { get; set; }
        public string Fax { get; set; }

        public virtual ICollection<Order> Orders { get; set; }
    }
}

NwindDataService.Invoices

using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using BlazorDemo.Data.Northwind;
using BlazorDemo.DataProviders;

namespace BlazorDemo.Services {
    public partial class NwindDataService {
        public Task<IEnumerable<Invoice>> GetInvoicesAsync(CancellationToken ct = default) {
            // Return your data here
        }
    }
}

NwindDataService.Customers

using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using BlazorDemo.Data.Northwind;
using BlazorDemo.DataProviders;

namespace BlazorDemo.Services {
    public partial class NwindDataService {
        public Task<IEnumerable<Customer>> GetCustomersAsync(CancellationToken ct = default) {
            // Return your data here
        }
    }
}

Program.cs

// ...
builder.Services.AddScoped<NwindDataService>();

Run Demo: Save and Restore the Layout View Example: Save and Load Layout Information View Example: Save and Load Extended Information about the Grid Layout

Implements

IEquatable<GridPersistentLayout>

Inheritance

Object

GridPersistentLayout

Footnotes

1. Filter criteria can be applied to grid data in the following ways:

   • A user changes the filter row filter.
   • The SetFilterCriteria or SetFieldFilterCriteria method is called.
   • A user applies a filter in a filter menu.

   Use the GetFilterCriteria() method to get the filter criteria currently applied to the grid data.

2. The saved layout does not include information about expanded rows in groups.