Saving Data to the View State

View state management provides client-based state management, where data is written into pages in hidden fields.

To save the data to the view state, set the IsTrackingViewState property for the active sheet to true, which is the default setting.

Advantages and Disadvantages

The advantages of using the view state are:

No server resources are required.
It requires less coding.
It requires less database access.
Spread manages all its data. The user changes are saved automatically to the component's data model.

The default control settings use the view state to save data. This default setting is best for small data models. If you are using larger data sets, you will probably want to use one of the other state management options

The disadvantage of using view state is the impact on performance. Because the view state is stored in the page itself, storing large values can cause the page to slow down when users display it and when they post it.

Return to the list of options in Maintaining State.

Using Code

Use the view state to save data.

Example

The following sample illustrates using the view state to save data.

C#	Copy Code
protected void Page_Load(object sender, System.EventArgs e) { if (this.IsPostBack) return; // Connect to NWIND MS Access example with OLE DB. OleDbConnection thisConnection = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0; Data Source=D:\\NWIND.MDB"); // Open connection. thisConnection.Open(); // Create DataSet to contain related data tables, rows, and columns. DataSet thisDataSet = new DataSet(); OleDbDataAdapter orderAdapter = new OleDbDataAdapter("SELECT EmployeeID, LastName, FirstName, Title FROM Employees", thisConnection); orderAdapter.Fill(thisDataSet, "Employees"); FpSpread1.ActiveSheetView.IsTrackingViewState = true; FpSpread1.ActiveSheetView.DataSource = thisDataSet; FpSpread1.ActiveSheetView.DataMember = "Employees"; thisConnection.Close(); thisConnection.Dispose(); }

Copy Code

protected void Page_Load(object sender, System.EventArgs e)
{
if (this.IsPostBack) return;
// Connect to NWIND MS Access example with OLE DB.
OleDbConnection thisConnection = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0; Data Source=D:\\NWIND.MDB");
// Open connection.
thisConnection.Open();
// Create DataSet to contain related data tables, rows, and columns.
DataSet thisDataSet = new DataSet();
OleDbDataAdapter orderAdapter = new OleDbDataAdapter("SELECT EmployeeID, LastName, FirstName, Title FROM Employees", thisConnection);
orderAdapter.Fill(thisDataSet, "Employees");
FpSpread1.ActiveSheetView.IsTrackingViewState = true;
FpSpread1.ActiveSheetView.DataSource = thisDataSet;
FpSpread1.ActiveSheetView.DataMember = "Employees";
thisConnection.Close();
thisConnection.Dispose();
}

VB	Copy Code
Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load If (Me.IsPostBack) Then Return ' Connect to NWIND MS Access example with OLE DB. Dim thisConnection As New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0; Data Source=D:\NWIND.MDB") ' Open connection. thisConnection.Open() ' Create DataSet to contain related data tables, rows, ' and columns. Dim thisDataSet As New DataSet() Dim orderAdapter As New OleDbDataAdapter("SELECT EmployeeID, LastName, FirstName, Title FROM Employees", thisConnection) orderAdapter.Fill(thisDataSet, "Employees") FpSpread1.ActiveSheetView.IsTrackingViewState = True FpSpread1.ActiveSheetView.DataSource = thisDataSet FpSpread1.ActiveSheetView.DataMember = "Employees" thisConnection.Close() thisConnection.Dispose() End Sub

Copy Code

 Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    If (Me.IsPostBack) Then Return
    
    ' Connect to NWIND MS Access example with OLE DB.
    Dim thisConnection As New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0; Data Source=D:\NWIND.MDB")
    ' Open connection.
    thisConnection.Open()
    ' Create DataSet to contain related data tables, rows,
    ' and columns.
    Dim thisDataSet As New DataSet()
    
    Dim orderAdapter As New OleDbDataAdapter("SELECT EmployeeID, LastName, FirstName, Title FROM Employees", thisConnection)
    orderAdapter.Fill(thisDataSet, "Employees")
    
    FpSpread1.ActiveSheetView.IsTrackingViewState = True
    FpSpread1.ActiveSheetView.DataSource = thisDataSet
    FpSpread1.ActiveSheetView.DataMember = "Employees"
    
    thisConnection.Close()
    thisConnection.Dispose()
 End Sub