ISpreadsheetValueStorage Interface

Declares members of the Spreadsheet editor’s value storage.

Namespace: DevExpress.ExpressApp.Office.Win

Assembly: DevExpress.ExpressApp.Office.Win.v23.2.dll

NuGet Package: DevExpress.ExpressApp.Office.Win

Declaration

C#

public interface ISpreadsheetValueStorage

VB.NET

Public Interface ISpreadsheetValueStorage

Remarks

A Spreadsheet editor’s value storage allows you to implement custom logic executed when saving or loading a Spreadsheet document. Follow the steps below to create a custom value storage that specifies a file storage format.

Tip

We recommend you to use the SpreadsheetPropertyEditor.DocumentFormat property to specify a document storage format (see How to: Customize the Spreadsheet Editor). The example below is shown for demonstration purposes.

1. Create a class that implements the ISpreadsheetValueStorage interface as shown below in the WinForms module project (MySolution.Module.Win). If your solution does not contain this project, add the Controller to the WinForms application project (MySolution.Win).

   C#

   using DevExpress.ExpressApp.Office.Win;
   using DevExpress.Spreadsheet;
   using DevExpress.XtraSpreadsheet;
   // ...
   public class OpenXmlSpreadsheetValueStorage : ISpreadsheetValueStorage {
       public object GetValue(SpreadsheetControl control) {
           return control.SaveDocument(DocumentFormat.OpenXml);
       }
       public void SetValue(SpreadsheetControl control, object propertyValue) {
           byte[] byteArray = propertyValue as byte[];
           if(byteArray != null) {
               control.LoadDocument(byteArray, DocumentFormat.OpenXml);
           }
       }
   }
   

   VB.NET

   Imports DevExpress.ExpressApp.Office.Win
   Imports DevExpress.Spreadsheet
   Imports DevExpress.XtraSpreadsheet
   ' ...
   Public Class OpenXmlSpreadsheetValueStorage
       Implements ISpreadsheetValueStorage
       Public Function GetValue(control As SpreadsheetControl) As Object _
       Implements ISpreadsheetValueStorage.GetValue
           Return control.SaveDocument(DocumentFormat.OpenXml)
       End Function 
       Public Sub SetValue(control As SpreadsheetControl, propertyValue As Object) _
       Implements ISpreadsheetValueStorage.SetValue
           Dim byteArray As Byte() = TryCast(propertyValue, Byte())
           If byteArray IsNot Nothing Then
               control.LoadDocument(byteArray, DocumentFormat.OpenXml)
           End If
       End Sub
   End Class
   

2. Create a View Controller and access the SpreadsheetPropertyEditor as described in the Ways to Access UI Elements and Their Controls topic. Set the editor’s ValueStorage property to an instance of CustomSpreadsheetValueStorage as shown below:

   C#

   using DevExpress.ExpressApp;
   using DevExpress.ExpressApp.Office.Win;
   // ...
   public class CustomSpreadsheetValueStorageController : ObjectViewController<DetailView, Document> {
       protected override void OnActivated() {
           base.OnActivated();
           SpreadsheetPropertyEditor spreadsheetPropertyEditor = View.FindItem("Data") as SpreadsheetPropertyEditor;
           if (spreadsheetPropertyEditor != null) {
               spreadsheetPropertyEditor.ValueStorage = new OpenXmlSpreadsheetValueStorage();
           }
       }
   }
   

   VB.NET

   Imports DevExpress.ExpressApp
   Imports DevExpress.ExpressApp.Office.Win
   ' ...
   Public Class CustomSpreadsheetValueStorageController
       Inherits ObjectViewController(Of DetailView, Document)
       Protected Overrides Sub OnActivated()
           MyBase.OnActivated()
           Dim spreadsheetPropertyEditor As SpreadsheetPropertyEditor = TryCast(View.FindItem("Data"), SpreadsheetPropertyEditor)
           If spreadsheetPropertyEditor IsNot Nothing Then
               spreadsheetPropertyEditor.ValueStorage = New OpenXmlSpreadsheetValueStorage()
           End If
       End Sub
   End Class