Localization - ASP.NET Web Forms Document Viewer

• Jul 20, 2026
• 4 minutes to read

To localize the Web Document Viewer, use the built-in localization mechanisms and substitute localization strings. Localization strings can be loaded either from JSON dictionary files, or using satellite resource assemblies.

For information on how to localize the DevExpress Web Forms controls, review the following help topic: Localization.

Use JSON Dictionaries

Tip

The component UI is built on DevExtreme widgets. To localize editors and client-side formatting of dates and numbers (outside the generated document), use DevExtreme localization and call DevExpress.localization.locale(<Locale>). For more information, review the following topic: DevExtreme - Localization and Globalization Overview.

Obtain Dictionaries

You need to load three JSON dictionaries:

1. <Locale>.json. Contains localization strings for DevExtreme editors used in the Reporting component. The dictionaries are available on GitHub. For more information, see DevExtreme jQuery - Localization and Globalization Overview.
2. dx-analytics-core.<Locale>.json. Contains core localization strings. This dictionary is included in a ZIP archive available from the DevExpress Localization Service. For more information, see DevExpress UI Localization Service (Maintenance Mode).
3. dx-reporting.<Locale>.json. Contains Document Viewer-specific localization strings. This dictionary is included in a ZIP archive available from the DevExpress Localization Service. For more information, see DevExpress UI Localization Service (Maintenance Mode).

In the file names above, the <Locale> is the locale of the dictionary contents.

Use Dictionaries

To localize the application UI, do the following:

1. Subscribe to the CustomizeLocalization event and load the dx-analytics-core.<Locale>.json and dx-reporting.<Locale>.json dictionaries using the LoadMessages(messages) method.

Use Satellite Resource Assemblies

You can localize the Web Document Viewer with the Satellite Resource Assemblies (libraries that contain translated resources).

For more information, review the following help topic: Localize ASP.NET Controls with Satellite Resource Assemblies.

Substitute Localization Strings

Use the UpdateLocalization method in the client-side ASPxClientWebDocumentViewer.CustomizeLocalization event handler to substitute a particular localization string with the specified text.

Tip

You can use the satellite resource assemblies to translate text strings and then adjust the translation by handling the CustomizeLocalization event.

ASPX

<script type="text/javascript" id="script"> 
    function customizeLocalization(s) {
        s.UpdateLocalization({
            'Search': 'Suche',
            'Search result': 'Suchergebnisse',
            'Next Page' : 'Nächste Seite',
            'Export Options' : 'Exportoptionen'
        });
    }
</script> 

<dx:ASPxWebDocumentViewer ID="ASPxWebDocumentViewer1" runat="server">
    <ClientSideEvents CustomizeLocalization="customizeLocalization"/>
</dx:ASPxWebDocumentViewer>

View Example: Reporting for Web Forms - Report Designer and Document Viewer Localization

Important

Localization strings are case sensitive. A string is translated if you use correct case to specify it.

On a web page localized string values may be capitalized differently. For example, the ‘Search result’ string is displayed as ‘SEARCH RESULT’.

To identify the localized string you want to change, locate the UI element in the browser’s Developer Tools, as shown in the following image:

Use UI Localization Client

The UI Localization Client is a cross-platform utility that helps you identify non-translated strings in DevExpress UI controls and translate them during a debug session. The utility generates RESX files with translated resources and adds them to the project. The UI Localization Client loads all Web Reporting resource strings after the controls are rendered and does not reflect later UI interactions.

For more information refer to the following topic: UI Localization Client.

The resource strings for the Web Reporting Controls (Web Document Viewer and Web Report Designer) are located in the following localization containers in the UI Localization Client window:

DevExpress.XtraReports.Web.Localization.LocalizationContainer

Contains localization strings specific only to the Web Reporting Controls.

DevExpress.Utils.Localization.CoreLibraryResources

Contains cross-platform localization strings used in the Web Reporting Controls.

DevExpress.Web.Resources.Localization.LocalizationContainer

Contains localization strings common to DevExpress Web Components used in the Web Reporting Controls.

Troubleshooting

If you followed the instructions in the UI Localization Client topic and the resource strings are still not visible, try clearing browser cache.

Identify Non-Translated Strings

• Use our UI Localization Client tool shipped as part of your DevExpress subscription. This tool streamlines the entire localization process. You can quickly find non-translated strings and translate them during a debug session.
• Handle the XtraLocalizer.QueryLocalizedStringNonTranslated event to collect non-localized resource strings for further translation. The event allows you to focus on strings that require translation in your application.