IUriProvider Interface

OBSOLETE

Please use the IUriProvider instead

Defines the provider of the locations for external objects in document export.

Namespace: DevExpress.XtraRichEdit.Services

Assembly: DevExpress.RichEdit.v19.2.Core.dll

Declaration

C#

[ComVisible(true)]
[Obsolete("Please use the DevExpress.Office.Services.IUriProvider instead", true)]
public interface IUriProvider :
    IUriProvider

VB.NET

<ComVisible(True)>
<Obsolete("Please use the DevExpress.Office.Services.IUriProvider instead", True)>
Public Interface IUriProvider
    Inherits IUriProvider

Remarks

When the document is exported to a format that implies that a part of the document’s content is located externally, such as HTML format, the IUriProvider interface provides Uniform Resource Locators (URI) for the external objects. The IUriProvider.CreateCssUri method processes the style information , and the IUriProvider.CreateImageUri processes images.

An object implementing the IUriProvider interface is specified as the parameter for the SubDocument.GetHtmlText method.

The following code snippet illustrates how to add a custom IUriProvider class instance to services, and implement its functionality to save CSS files and provide unique names for image files.

This example demonstrates how to use the DocumentImage.Uri property to set the image’s src attribute when a document is saved in HTML format. You can switch on the HtmlDocumentExporterOptions.EmbedImages option to observe that the custom URI provider is idle for embedded images.

Note

The complete sample project How to retain the original image URI in an HTML document is available in the DevExpress Examples repository.

Form1.cs

using DevExpress.Office.Services;
using DevExpress.XtraRichEdit.API.Native;
using DevExpress.XtraRichEdit.Export;
using System;
// ...
        private void richEditControl1_DocumentLoaded(object sender, EventArgs e)
        {
            IUriProviderService service = richEditControl1.GetService<IUriProviderService>();
            if (service != null) {
                service.RegisterProvider(new CustomUriProvider());
            }
        }
        private void richEditControl1_ContentChanged(object sender, EventArgs e)
        {
            ReloadHtml();
        }

        private void ReloadHtml()
        {
            HtmlDocumentExporterOptions exportOptions = new HtmlDocumentExporterOptions();
            exportOptions.EmbedImages = embedImagesCheck.Checked;
            string sText = richEditControl1.Document.GetHtmlText(richEditControl1.Document.Range, new CustomUriProvider(), exportOptions);
            memoEdit1.Text = sText;
        }

Form1.vb

Imports DevExpress.Office.Services
Imports DevExpress.XtraRichEdit.API.Native
Imports DevExpress.XtraRichEdit.Export
Imports System
' ...
        Private Sub richEditControl1_DocumentLoaded(ByVal sender As Object, ByVal e As EventArgs) Handles richEditControl1.DocumentLoaded
            Dim service As IUriProviderService = richEditControl1.GetService(Of IUriProviderService)()
            If service IsNot Nothing Then
                service.RegisterProvider(New CustomUriProvider())
            End If
        End Sub

        Private Sub richEditControl1_ContentChanged(ByVal sender As Object, ByVal e As EventArgs)
            ReloadHtml()
        End Sub

        Private Sub ReloadHtml()
            Dim exportOptions As New HtmlDocumentExporterOptions()
            exportOptions.EmbedImages = embedImagesCheck.Checked
            Dim sText As String = richEditControl1.Document.GetHtmlText(richEditControl1.Document.Range, New CustomUriProvider(), exportOptions)
            memoEdit1.Text = sText
        End Sub

CustomUriProvider.cs

using DevExpress.Office.Services;
using DevExpress.Office.Utils;
using System;
// ...
     public class CustomUriProvider : IUriProvider
     {
        public string CreateCssUri(string rootUri, string styleText, string relativeUri)
        {
            return String.Empty;
        }

        public string CreateImageUri(string rootUri, OfficeImage image, string relativeUri)
        {
            return image.Uri;
        }
    }

CustomUriProvider.vb

Imports DevExpress.Office.Services
Imports DevExpress.Office.Utils
Imports System
' ...
    Public Class CustomUriProvider
        Implements IUriProvider

        Public Function CreateCssUri(ByVal rootUri As String, ByVal styleText As String, ByVal relativeUri As String) As String Implements IUriProvider.CreateCssUri
            Return String.Empty
        End Function

        Public Function CreateImageUri(ByVal rootUri As String, ByVal image As OfficeImage, ByVal relativeUri As String) As String Implements IUriProvider.CreateImageUri
            Return image.Uri
        End Function
    End Class

This example implements the IUriProvider descendant and use it in the GetHtmlText(DocumentRange, IUriProvider, HtmlDocumentExporterOptions) method call.

Note

The complete sample project How to save the document range in different formats is available in the DevExpress Examples repository.

Form1.cs

public class CustomUriProvider : DevExpress.Office.Services.IUriProvider
{
    string rootDirectory;
    public CustomUriProvider(string rootDirectory)
    {
        if (String.IsNullOrEmpty(rootDirectory))
            DevExpress.Office.Utils.Exceptions.ThrowArgumentException("rootDirectory", rootDirectory);
        this.rootDirectory = rootDirectory;
    }

    public string CreateCssUri(string rootUri, string styleText, string relativeUri)
    {
        string cssDir = String.Format("{0}\\{1}", this.rootDirectory, rootUri.Trim('/'));
        if (!Directory.Exists(cssDir))
            Directory.CreateDirectory(cssDir);
        string cssFileName = String.Format("{0}\\style.css", cssDir);
        File.AppendAllText(cssFileName, styleText);
        return GetRelativePath(cssFileName);
    }
    public string CreateImageUri(string rootUri, DevExpress.Office.Utils.OfficeImage image, string relativeUri)
    {
        string imagesDir = String.Format("{0}\\{1}", this.rootDirectory, rootUri.Trim('/'));
        if (!Directory.Exists(imagesDir))
            Directory.CreateDirectory(imagesDir);
        string imageName = String.Format("{0}\\{1}.png", imagesDir, Guid.NewGuid());
        image.NativeImage.Save(imageName, ImageFormat.Png);
        return GetRelativePath(imageName);
    }
    string GetRelativePath(string path)
    {
        string substring = path.Substring(this.rootDirectory.Length);
        return substring.Replace("\\", "/").Trim('/');
    }
}

Form1.vb

    Public Class CustomUriProvider
        Implements DevExpress.Office.Services.IUriProvider

        Private rootDirecory As String
        Public Sub New(ByVal rootDirectory As String)
            If String.IsNullOrEmpty(rootDirectory) Then
                DevExpress.Office.Utils.Exceptions.ThrowArgumentException("rootDirectory", rootDirectory)
            End If
            Me.rootDirecory = rootDirectory
        End Sub

        Public Function CreateCssUri(ByVal rootUri As String, ByVal styleText As String, ByVal relativeUri As String) As String Implements DevExpress.Office.Services.IUriProvider.CreateCssUri
            Dim cssDir As String = String.Format("{0}\{1}", Me.rootDirecory, rootUri.Trim("/"c))
            If Not Directory.Exists(cssDir) Then
                Directory.CreateDirectory(cssDir)
            End If
            Dim cssFileName As String = String.Format("{0}\style.css", cssDir)
            File.AppendAllText(cssFileName, styleText)
            Return GetRelativePath(cssFileName)
        End Function
        Public Function CreateImageUri(ByVal rootUri As String, ByVal image As DevExpress.Office.Utils.OfficeImage, ByVal relativeUri As String) As String Implements DevExpress.Office.Services.IUriProvider.CreateImageUri
            Dim imagesDir As String = String.Format("{0}\{1}", Me.rootDirecory, rootUri.Trim("/"c))
            If Not Directory.Exists(imagesDir) Then
                Directory.CreateDirectory(imagesDir)
            End If
            Dim imageName As String = String.Format("{0}\{1}.png", imagesDir, Guid.NewGuid())
            image.NativeImage.Save(imageName, ImageFormat.Png)
            Return GetRelativePath(imageName)
        End Function
        Private Function GetRelativePath(ByVal path As String) As String
            Dim substring As String = path.Substring(Me.rootDirecory.Length)
            Return substring.Replace("\", "/").Trim("/"c)
        End Function
    End Class