How to persist RadGrid Sorting

[Herman Gouw]

Hi,

In my current project, I have to write a web page containing a RadGrid with Persisted Sorting.

I have implement the web page similar to as follows RadGrid with Persisted Sorting

The RadGrid's SortExpressions are persisted in the Settings which are saved (i.e. serialized) on Page_UnLoad and loaded (i.e. deserialized) on Page_Load.

I created the class SortExpressions instead of using Telerik's GridSortExpression because GridSortExpression is not marked as Serializable.

The web page works as expected. However, can you please review my code if I have implemented it correctly?

The code is given as follows:

ASPX

<form id="form1" runat="server">
<div>
    <telerik:RadScriptManager ID="radScriptManager" runat="server" />
    <telerik:RadGrid ID="radGrid" AutoGenerateColumns="false" AllowSorting="true" OnNeedDataSource="radGrid_NeedDataSource" runat="server">
        <ClientSettings>
            <Scrolling UseStaticHeaders="true" />
        </ClientSettings>
        <MasterTableView AllowMultiColumnSorting="true" TableLayout="Fixed">
            <Columns>
                <telerik:GridBoundColumn DataField="Name" DataType="System.String" HeaderText="Name" HeaderStyle-HorizontalAlign="Center" ItemStyle-HorizontalAlign="Center" SortExpression="Name" AllowSorting="true" UniqueName="Name" />
                <telerik:GridBoundColumn DataField="Founder" DataType="System.String" HeaderText="Founder" HeaderStyle-HorizontalAlign="Center" ItemStyle-HorizontalAlign="Center" SortExpression="Founder" AllowSorting="true" UniqueName="Founder" />
            </Columns>
        </MasterTableView>
    </telerik:RadGrid>
</div>
</form>

C#

public partial class RadGridWithSorting : Page
{
    private const string SettingsFilename = "Settings.bin";
    private Settings _settings = null;
    private List<Company> _companies = null;

    protected Settings Settings
    {
        get
        {
            if (this._settings == null)
            {
                this._settings = new Settings();
            }
            return this._settings;
        }
        set
        {
            this._settings = value;
        }
    }

    protected void Page_Load(object sender, EventArgs e)
    {
        LoadSettings();
        LoadSortExpressions();

        if (!IsPostBack)
        {
            this._companies = Company.Load();
            Session["COMPANIES"] = this._companies;
        }
        else
        {
            this._companies = (List<Company>)Session["COMPANIES"];
        }
    }

    protected void Page_UnLoad(object sender, EventArgs e)
    {
        SaveSortExpressions();
        SaveSettings();
    }

    protected void radGrid_NeedDataSource(object source, GridNeedDataSourceEventArgs e)
    {
        this.radGrid.DataSource = this._companies;
    }

    private void LoadSettings()
    {
        Settings = Helper.Load(SettingsFilename);
    }

    private void LoadSortExpressions()
    {
        this.radGrid.MasterTableView.SortExpressions.Clear();
        foreach (SortExpression sortExpression in Settings.SortExpressions)
        {
            GridSortExpression gridSortExpression = new GridSortExpression();
            gridSortExpression.FieldName = sortExpression.FieldName;
            gridSortExpression.SortOrder = sortExpression.SortOrder;
            this.radGrid.MasterTableView.SortExpressions.AddSortExpression(gridSortExpression);
        }
    }

    private void SaveSettings()
    {
        Helper.Save(Settings, SettingsFilename);
    }

    private void SaveSortExpressions()
    {
        Settings.SortExpressions.Clear();
        foreach (GridSortExpression sortExpression in this.radGrid.MasterTableView.SortExpressions)
        {
            Settings.SortExpressions.Add(new SortExpression(sortExpression.FieldName, sortExpression.SortOrder));
        }
    }
}

[Serializable]
public class Settings
{
    public List<SortExpression> SortExpressions { get; set; }

    public Settings()
    {
        SortExpressions = new List<SortExpression> {};
    }
    public Settings(List<SortExpression> sortExpressions)
    {
        SortExpressions = sortExpressions;
    }
}

[Serializable]
public class SortExpression
{
    public string FieldName { get; set; }
    public GridSortOrder SortOrder { get; set; }

    public SortExpression()
    {
        FieldName = null;
        SortOrder = GridSortOrder.None;
    }
    public SortExpression(string fieldName, GridSortOrder sortOrder)
    {
        FieldName = fieldName;
        SortOrder = sortOrder;
    }
}

Thanks,

Herman

[Pavlina]

Hi Herman,

I went through your code and it looks correct. However, I suggest that you review the following online example which demonstrates saving and restoring RadGrid settings by user.
http://demos.telerik.com/aspnet-ajax/grid/examples/programming/savinggridsettingsonperuserbasis/defaultcs.aspx

Greetings,
Pavlina
the Telerik team

[Herman Gouw]

Thanks Pavlina.