Saving Grid Settings on a Per User Basis
This approach is obsoleted. In case you need to persist the grid's setting we strongly recommend to use RadPersistenceManager control.
Following is a small application that demonstrates a way to persist runtime settings of Telerik RadGrid in a variety of formats. You can persist the extracted settings on any medium - session, application variables, database, etc. For your convenience, the functionality is isolated in a single class called GridSettingsPersister. It is designed to save from and load into Telerik RadGrid the following runtime settings:
-
Page size
-
Group-by expressions
-
Sort expressions
-
Filter expression
-
Column settings
-
Width
-
OrderIndex
-
Display
-
Visible
-
CurrentFilterFunction
-
CurrentFilterValue
How to save grid settings
To use the persister, create a new instance of the GridSettingsPersister class, passing the RadGrid instance whose settings will be imported/exported in the constructor. To extract and serialize the current grid settings into a string, call the SaveSettings method of the object. Alternatively, you can use the GetSavedSettings method to retrieve the extracted settings as an instance of GridSettingsCollection. Instances of this class can serialize themselves to either a string or a byte array using the ToString and ToArray methods, respectively. Thus, you have the flexibility to save the extracted settings in one of the 3 formats:
-
string - settings are serialized to a string, much like the ViewState mechanism
-
byte[] - settings are serialized to a byte array
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GridSettingsCollection instance - settings are not serialized and can be saved as an object
To save RadGrid's settings, call the SaveSettings method of the persister after making sure no further changes to RadGrid will be made. In a regular page life cycle, use the Page_PreRender method of the Page, or override and use the Render method for this purpose.
How to load grid settings
To load settings into the RadGrid instance, call the LoadSettings method of the GridSettingsPersister instance, passing the settings in one of the 3 accepted types:
-
string - settings serialized to a string
-
byte[] - settings serialized to a byte array
-
GridSettingsCollection instance - original non-serialized settings container
To load settings on initial page load, use the Init or Load events of the page to call LoadSettings. If RadGrid is databound in any of these, make sure you load the settings before binding the grid. Alternatively, if you are loading grid settings in a postback event of another control, call RadGrid.Rebind() to apply the restored settings.
See it in action
To see the GridSettingsPersister in action, please visit the Persisting Grid Settings online demo.
Show me the code
Following is the definition of the GridSettingsPersister class along with a couple of other helper classes that implement setting persistence for RadGrid:
/// <summary>
/// Imports and exports settings from a RadGrid instance.
/// </summary>
public class GridSettingsPersister
{
public GridSettingsPersister()
: this(null)
{
}
/// <summary>
/// Initializes an instance of GridSettingsPersister from a RadGrid instance
/// </summary>
/// <param name="grid">The RadGrid instance to import and exports settings</param>
public GridSettingsPersister(RadGrid grid)
: this(grid, GridSettingsType.All)
{
}
/// <summary>
/// Initializes an instance of GridSettingsPersister from a RadGrid instance
/// and a collection GridSettingsType values
/// </summary>
/// <param name="grid">The RadGrid instance to import and exports settings</param>
/// <param name="persistedSettings">
/// A collection of GridSettingType values specifying the type of grid settings
/// to import or export
/// </param>
public GridSettingsPersister(RadGrid grid, GridSettingsType persistedSettingFlags)
{
_grid = grid;
_persistedSettingTypes = persistedSettingFlags;
_settings = new GridSettingsCollection();
_settings.ColumnSettings = new List<ColumnSettings>();
_settings.AutoGeneratedColumnSettings = new List<ColumnSettings>();
}
private RadGrid _grid;
private GridSettingsType _persistedSettingTypes;
private GridSettingsCollection _settings;
/// <summary>
/// The underlyiong RadGrid instance to import or export settings from
/// </summary>
public RadGrid Grid
{
get
{
return _grid;
}
set
{
_grid = value;
}
}
/// <summary>
/// Gets or sets the GridSettingType flags that specify the grid settings to
/// export or import
/// </summary>
public virtual GridSettingsType PersistedSettingTypes
{
get
{
return _persistedSettingTypes;
}
set
{
_persistedSettingTypes = value;
}
}
protected virtual GridSettingsCollection Settings
{
get
{
return _settings;
}
set
{
_settings = value;
}
}
/// <summary>
/// Saves the current grid settings and returns the settings serilized to string
/// </summary>
public virtual string SaveSettings()
{
return GetSavedSettings().ToString();
}
/// <summary>
/// Saves the current grid settings and retrieves the underlying
/// GridSettingsCollection instance that contains the grid settings
/// </summary>
public virtual GridSettingsCollection GetSavedSettings()
{
if (Grid == null)
{
throw new NullReferenceException();
}
if (IsSettingSpecified(GridSettingsType.Paging))
SavePagingSettings();
if (IsSettingSpecified(GridSettingsType.Grouping))
SaveGroupByExpressions();
if (IsSettingSpecified(GridSettingsType.Sorting))
SaveSortExpressions();
if (IsSettingSpecified(GridSettingsType.Filtering))
SaveFilterExpression();
if (IsSettingSpecified(GridSettingsType.ColumnSettings))
SaveColumnSettings();
return Settings;
}
protected bool IsSettingSpecified(GridSettingsType settingType)
{
return (PersistedSettingTypes & GridSettingsType.All) == GridSettingsType.All ||
(PersistedSettingTypes & settingType) == settingType;
}
protected virtual void SavePagingSettings()
{
Settings.PageSize = Grid.PageSize;
}
protected virtual void SaveGroupByExpressions()
{
Settings.GroupByExpressionsStates = new object[Grid.MasterTableView.GroupByExpressions.Count];
for (int i = 0; i < Settings.GroupByExpressionsStates.Length; i++)
{
Settings.GroupByExpressionsStates[i] = ((IStateManager)Grid.MasterTableView.GroupByExpressions[i]).SaveViewState();
}
}
protected virtual void SaveSortExpressions()
{
Settings.SortExpressionsState = ((IStateManager)Grid.MasterTableView.SortExpressions).SaveViewState();
}
protected virtual void SaveFilterExpression()
{
Settings.FilterExpression = Grid.MasterTableView.FilterExpression;
}
protected virtual void SaveColumnSettings()
{
Settings.ColumnSettings.Clear();
foreach (GridColumn column in Grid.MasterTableView.Columns)
{
Settings.ColumnSettings.Add(GetColumnSettings(column));
}
Settings.AutoGeneratedColumnSettings.Clear();
foreach (GridColumn column in Grid.MasterTableView.AutoGeneratedColumns)
{
Settings.AutoGeneratedColumnSettings.Add(GetColumnSettings(column));
}
}
private ColumnSettings GetColumnSettings(GridColumn column)
{
ColumnSettings colSettings = new ColumnSettings();
colSettings.UniqueName = column.UniqueName;
colSettings.Width = column.HeaderStyle.Width;
colSettings.Visible = column.Visible;
colSettings.Display = column.Display;
colSettings.OrderIndex = column.OrderIndex;
colSettings.CurrentFilterFunction = column.CurrentFilterFunction;
colSettings.CurrentFilterValue = column.CurrentFilterValue;
return colSettings;
}
private void SetColumnSettings(ref GridColumn column, ColumnSettings setting)
{
column.Display = setting.Display;
column.Visible = setting.Visible;
column.HeaderStyle.Width = setting.Width;
column.OrderIndex = setting.OrderIndex;
column.CurrentFilterFunction = setting.CurrentFilterFunction;
column.CurrentFilterValue = setting.CurrentFilterValue;
}
/// <summary>
/// Loads grids settings from a serialized string
/// </summary>
/// <param name="value">The string that contains the serialized settings</param>
public virtual void LoadSettings(string value)
{
LoadSettings(GridSettingsCollection.LoadFromSerializedData(value));
}
/// <summary>
/// Loads grids settings from a byte array
/// </summary>
/// <param name="data">The byte array that contains the serialized grid settings</param>
public virtual void LoadSettings(byte[] data)
{
LoadSettings(GridSettingsCollection.LoadFromSerializedData(data));
}
/// <summary>
/// Loads grid settings from a GridSettingsCollection instance
/// </summary>
/// <param name="settings">The GridSettingsCollection instance to load settings from</param>
public virtual void LoadSettings(GridSettingsCollection settings)
{
if (Grid == null || settings == null)
{
throw new NullReferenceException();
}
Settings = settings;
if (IsSettingSpecified(GridSettingsType.Paging))
LoadPagingSettings();
if (IsSettingSpecified(GridSettingsType.Grouping))
LoadGroupByExpressions();
if (IsSettingSpecified(GridSettingsType.Sorting))
LoadSortExpressions();
if (IsSettingSpecified(GridSettingsType.Filtering))
LoadFilterExpression();
if (IsSettingSpecified(GridSettingsType.ColumnSettings))
LoadColumnSettings();
}
protected virtual void LoadPagingSettings()
{
if (Grid.AllowPaging && Settings.PageSize > 0)
{
Grid.PageSize = Settings.PageSize;
}
}
protected virtual void LoadGroupByExpressions()
{
if (Settings.GroupByExpressionsStates == null)
return;
Grid.MasterTableView.GroupByExpressions.Clear();
foreach (object expressionState in Settings.GroupByExpressionsStates)
{
GridGroupByExpression expression = new GridGroupByExpression();
((IStateManager)expression).LoadViewState(expressionState);
Grid.MasterTableView.GroupByExpressions.Add(expression);
}
}
protected virtual void LoadSortExpressions()
{
if (Settings.SortExpressionsState == null)
return;
((IStateManager)Grid.MasterTableView.SortExpressions).LoadViewState(Settings.SortExpressionsState);
}
protected virtual void LoadFilterExpression()
{
Grid.MasterTableView.FilterExpression = Settings.FilterExpression;
}
protected virtual void LoadColumnSettings()
{
if (Settings.AutoGeneratedColumnSettings.Count > 0)
{
Grid.ColumnCreated += new GridColumnCreatedEventHandler(Grid_ColumnCreated);
}
foreach (ColumnSettings colSetting in Settings.ColumnSettings)
{
GridColumn column = Grid.MasterTableView.GetColumnSafe(colSetting.UniqueName);
if (column != null)
{
SetColumnSettings(ref column, colSetting);
}
}
}
private void Grid_ColumnCreated(object sender, GridColumnCreatedEventArgs e)
{
ColumnSettings settings = Settings.AutoGeneratedColumnSettings.Find(delegate(ColumnSettings set)
{
return set.UniqueName == e.Column.UniqueName;
});
GridColumn column = e.Column;
if (settings != null)
{
SetColumnSettings(ref column, settings);
}
}
}
/// <summary>
/// Enumerates the types of grid settings that can be persisted
/// </summary>
[Flags]
public enum GridSettingsType
{
Paging = 1,
Sorting = 2,
Filtering = 4,
Grouping = 8,
ColumnSettings = 16,
All = 32
}
/// <summary>
/// Represents a collection of grid settings
/// </summary>
[Serializable]
public class GridSettingsCollection
{
private int _pageSize;
private object[] _groupByExpressionsStates;
private object _sortExpressionsState;
private string _filterExpression;
private List<ColumnSettings> _columnSettings;
private List<ColumnSettings> _autoColumnSettings;
public int PageSize
{
get
{
return _pageSize;
}
set
{
_pageSize = value;
}
}
public object[] GroupByExpressionsStates
{
get
{
return _groupByExpressionsStates;
}
set
{
_groupByExpressionsStates = value;
}
}
public object SortExpressionsState
{
get
{
return _sortExpressionsState;
}
set
{
_sortExpressionsState = value;
}
}
public string FilterExpression
{
get
{
return _filterExpression;
}
set
{
_filterExpression = value;
}
}
public List<ColumnSettings> ColumnSettings
{
get
{
return _columnSettings;
}
set
{
_columnSettings = value;
}
}
public List<ColumnSettings> AutoGeneratedColumnSettings
{
get
{
return _autoColumnSettings;
}
set
{
_autoColumnSettings = value;
}
}
/// <summary>
/// Returns the serialized object as string
/// </summary>
public override string ToString()
{
LosFormatter formatter = new LosFormatter();
StringWriter writer = new StringWriter();
formatter.Serialize(writer, this);
return writer.ToString();
}
/// <summary>
/// Returns the serialized object as byte array
/// </summary>
public byte[] ToArray()
{
LosFormatter formatter = new LosFormatter();
MemoryStream stream = new MemoryStream();
formatter.Serialize(stream, this);
return stream.ToArray();
}
/// <summary>
/// Gets the GridSettingsCollectionInstance from its serialized string data
/// </summary>
/// <param name="data">The object as serialized string data</param>
public static GridSettingsCollection LoadFromSerializedData(string data)
{
LosFormatter formatter = new LosFormatter();
return (GridSettingsCollection)formatter.Deserialize(data);
}
/// <summary>
/// Gets the GridSettingsCollectionInstance from its serialized byte array
/// </summary>
/// <param name="data">The object as serialized byte array</param>
public static GridSettingsCollection LoadFromSerializedData(byte[] data)
{
LosFormatter formatter = new LosFormatter();
MemoryStream stream = new MemoryStream(data);
return (GridSettingsCollection)formatter.Deserialize(stream);
}
}
/// <summary>
/// Represents a collection of grid column settings
/// </summary>
[Serializable]
public class ColumnSettings
{
private string _uniqueName;
private int _orderIndex;
private Unit _width;
private bool _visible;
private bool _display;
private GridKnownFunction _currentFilterFunction;
private string _currentFilterValue;
public string UniqueName
{
get
{
return _uniqueName;
}
set
{
_uniqueName = value;
}
}
public int OrderIndex
{
get
{
return _orderIndex;
}
set
{
_orderIndex = value;
}
}
public Unit Width
{
get
{
return _width;
}
set
{
_width = value;
}
}
public bool Visible
{
get
{
return _visible;
}
set
{
_visible = value;
}
}
public bool Display
{
get
{
return _display;
}
set
{
_display = value;
}
}
public GridKnownFunction CurrentFilterFunction
{
get
{
return _currentFilterFunction;
}
set
{
_currentFilterFunction = value;
}
}
public string CurrentFilterValue
{
get
{
return _currentFilterValue;
}
set
{
_currentFilterValue = value;
}
}
}You can extend the logic and store the user preferences via Profile object (part of ASP.NET 2.0). Thus the settings will be preserved not only for the current user session but for subsequent sessions as well. More details are available in this code library thread.