IWebRichTextValueStorage Interface

Declares members of the Rich Text editor’s value storage.

Namespace: DevExpress.ExpressApp.Office.Web

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

NuGet Package: DevExpress.ExpressApp.Office.Web

Declaration

C#

public interface IWebRichTextValueStorage

VB.NET

Public Interface IWebRichTextValueStorage

Remarks

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

1. In the ASP.NET Web Forms Module project, create a class that implements the IWebRichTextValueStorage interface as shown below:

   C#

   using DevExpress.ExpressApp.Office.Web;
   using DevExpress.Web.ASPxRichEdit;
   using DevExpress.XtraRichEdit;
   using System.IO;
   // ...
   public class WebMhtRichTextValueStorage : IWebRichTextValueStorage {
       public object GetValue(ASPxRichEdit control) {
           using (MemoryStream memoryStream = new MemoryStream()) {
               control.SaveCopy(memoryStream, DocumentFormat.MhtText);
               using (StreamReader streamReader = new StreamReader(memoryStream)) {
                   memoryStream.Seek(0, SeekOrigin.Begin);
                   return streamReader.ReadToEnd();
               }
           }
       }
       public void SetValue(ASPxRichEdit control, object propertyValue, string documentID) {
           control.Open(documentID, DocumentFormat.MhtText, () => (byte[])propertyValue);
       }
   }
   

   VB.NET

   Imports DevExpress.ExpressApp.Office.Web
   Imports DevExpress.Web.ASPxRichEdit
   Imports DevExpress.XtraRichEdit
   Imports System.IO
   ' ...
   Public Class WebMhtRichTextValueStorage
       Implements IWebRichTextValueStorage
       Public Function GetValue(ByVal control As ASPxRichEdit) As Object _
           Implements IWebRichTextValueStorage.GetValue
           Using memoryStream As New MemoryStream()
               control.SaveCopy(memoryStream, DocumentFormat.MhtText)
               Using streamReader As New StreamReader(memoryStream)
                   memoryStream.Seek(0, SeekOrigin.Begin)
                   Return streamReader.ReadToEnd()
               End Using
           End Using
       End Function
       Public Sub SetValue(ByVal control As ASPxRichEdit, ByVal propertyValue As Object, ByVal documentID As String) _
           Implements IWebRichTextValueStorage.SetValue
           control.Open(documentID, DocumentFormat.MhtText, Function() DirectCast(propertyValue, Byte()))
       End Sub
   End Class
   

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

   C#

   using DevExpress.ExpressApp;
   using DevExpress.ExpressApp.Office.Web;
   // ...
   public class WebRichTextValueStorageController : ObjectViewController<DetailView, Document> {
       protected override void OnActivated() {
           base.OnActivated();
           ASPxRichTextPropertyEditor richTextPropertyEditor = View.FindItem("Text") as ASPxRichTextPropertyEditor;
           if (richTextPropertyEditor != null) {
               richTextPropertyEditor.ValueStorage = new WebMhtRichTextValueStorage();
           }
       }
   }
   

   VB.NET

   Imports DevExpress.ExpressApp
   Imports DevExpress.ExpressApp.Office.Web
   ' ...
   Public Class WebRichTextValueStorageController
       Inherits ObjectViewController(Of DetailView, Document)
       Protected Overrides Sub OnActivated()
           MyBase.OnActivated()
           Dim richTextPropertyEditor As ASPxRichTextPropertyEditor = TryCast(View.FindItem("Text"), ASPxRichTextPropertyEditor)
           If richTextPropertyEditor IsNot Nothing Then
               richTextPropertyEditor.ValueStorage = New WebMhtRichTextValueStorage()
           End If
       End Sub
   End Class