Web resources in model-driven apps
Web resources are virtual files that are stored in the Microsoft Dataverse database and that you can retrieve by using a unique URL address.
Note
IFRAMEing content that is behind an authentication boundary isn't supported through web resources or Power Apps component framework. Some embedded IFRAMEs might work in a browser client if the user directly logs into the external service, but this isn't supported in mobile or tablet applications. The specific scenario of embedding a form within an IFRAME, embedded in another form, isn't supported. We recommend the use of form as a component for such scenarios.
In general, use of Power Apps component framework and custom pages is encouraged to build configurable, reusable, and tighter external integrations. More information: IFRAME component
Capabilities of web resources
Web resources represent files that can be used to extend the Dataverse web application such as html files, JavaScript,
and CSS, and several image formats. You can use web resources in form customizations, the SiteMap, or the application
ribbon because they can be referenced by using URL syntax.
The URL syntax for web resources allows for relative path references. With your development tools, you can create a group of interdependent files on a development server by using file types compatible with web resources. Then, if you use a consistent naming convention and relative path references, the website will function after you upload all the files into Dataverse.
Because web resources are stored in Dataverse and are solution components, they can be easily exported and installed to other Dataverse orgs. Web resources are also available to users of Dataverse for Microsoft Office Outlook with Offline Access when offline because they're synchronized with the user's data.
You can use the form editor to add and configure form-enabled web resources into your forms.
Because web resources are stored as records in the database, they can be managed programmatically by using the standard techniques to create, retrieve, and update records. Text-based web resources (JScript, CSS, XML, XSL, RESX, and HTML) can be edited and saved in the application.
Limitations of web resources
There's no type of web resource that supports the capabilities of an ASP.NET(.aspx) page to execute code on the server. Web resources are limited to static files or files that are processed in the browser. A web resource can contain code that is processed in the browser to execute web service calls to interact with Dataverse data.
Web resources are only available by using the Dataverse web application security context. Only licensed Dataverse users who have the necessary privileges can access them.
Size limitations
The Organization.MaxUploadFileSize property determines maximum size of files that can be uploaded. This property is set in the Email tab of the System Settings in the Dynamics 365 application. This setting limits the size of files that can be attached to email messages, notes, and web resources. The default setting is 5 MB. Learn more about environment settings and file size limits
Web resource types
You can use 10 file formats to create web resources. The following table lists each file format, the allowed file extensions, and the type value that you use for each.
| File | File extensions | Type |
|---|---|---|
| Webpage (HTML) | .htm, .html | 1 |
| Style Sheet (CSS) | .css | 2 |
| Script (JScript) | .js | 3 |
| Data (XML) | .xml | 4 |
| Image (PNG) | .png | 5 |
| Image (JPG) | .jpg | 6 |
| Image (GIF) | .gif | 7 |
| Silverlight (XAP) | .xap | 8 |
| StyleSheet (XSL) | .xsl, .xslt | 9 |
| Image (ICO) | .ico | 10 |
| Vector format (SVG) | .svg | 11 |
| String (RESX) | .resx | 12 |
Reference web resources
There are several methods that you can use to reference web resources.
Note
When possible, use the $webresource directive. Only references that use the $webresource directive in the site map or
ribbon commands establish dependencies. Dependencies aren't created when web resources reference each other.
$webresource directive
You should always use the $webresource directive when referencing a web resource from a ribbon control or from
a SiteMap sub area. Use the $webresource directive anywhere the XML allows a URL value. The following sample shows how to use it.
$webresource:<name of Web Resource>
Note
When you use the $webresource directive, Dataverse creates or updates solution dependencies.
Xrm.Navigation.openWebResource
The Xrm.Navigation.openWebResource function opens an HTML web resource in a new window with parameters to pass the name of the web resource, any query string data to be passed in the data parameter, and information about height and width of the window.
The URL generated includes the unique GUID token so that the cached web resource loads.
Relative URL
When referencing a web resource from areas that don't support using the $webresource: directive, use a relative URL.
To enable this, we recommend that you use a consistent naming convention for the web resources that reflect a virtual file structure.
The solution publisher's customization prefix is included as a prefix to the name of the web resource.
This can represent a virtual "root" folder for all web resources added by that publisher.
You can then use the forward slash character (/) to simulate a folder structure that is honored by the web server.
From another web resource, you should always use relative URLs to reference each other.
For example, for the web page web resource new_/content/contentpage.htm to reference the
CSS web resource new_/Styles/styles.css, create the link as follows:
<link rel="stylesheet" type="text/css" href="../styles/styles.css" />
For the web page web resource new_/content/contentpage.htm to open the webpage web resource isv_/foldername/dialogpage.htm,
create the link as follows:
<a href="../../isv_/foldername/dialogpage.htm">Dialog Page</a>
Note
Don't use a relative URL using the WebResources folder as the root path for the URL.
For example, don't use: /WebResources/<name of web resource>. When a user belongs to more than one organization on a server,
this path refers to the users default organization. If the user isn't using their default organization and the
expected web resource isn't included in the user's default organization, a "File Not Found" error occurs even though the
web resource does occur in the organization the user is currently working in.
Full URL
The following sample shows the style of URL you can use to view web resources.
<Dataverse Environment URL>/WebResources/<name of web resource>
The application processes this URL and return the file that contains the latest version of the web resource. This URL looks like this:
<Dataverse Environment URL>/%7B<version value>%7D/WebResources/<name of web resource>
The version value is updated when you publish customizations and ensures that the browser uses the latest cached version of the web resource. Because of this, use a relative path to a web resource, the Xrm.Navigation.openWebResource function, or the $webresource Directive (when possible) because the version value is included. For large web resources there can be significant performance implications if you don't use the cached version of the file.
The following sample shows a URL for Dataverse, where MyOrganization is the name of your Dataverse Environment, and new_/test/test.htm
is the name of the web resource:
https://MyOrganization.crm.dynamics.com/WebResources/new_/test/test.htm
Note
Including the '/' character and a file name extension in the name of the web resource is an optional best practice. When you write code to reference a web resource that works for Dataverse, you should use the getClientUrl function.
Layout differences between the legacy web client and Unified Interface
A web resource control configured to use a certain number of rows have different heights in a Unified Client application compared to a web client application. This is because there's a difference in the height of a row between Unified Interface and web client. If a form is needed in both the web client and Unified Interface, you can use different forms in the Unified Interface app and the web client app with the control configured to use the appropriate number of rows in each form.
Community tools
WebResources Manager is a tool that XrmToolbox community developed for Dataverse. See the Developer tools article for community developed tools.
Note
The community tools are not a product of Dataverse and Microsoft does not extend support to the community tools. If you have questions pertaining to the tool, please contact the publisher. More Information: XrmToolBox.
See also
Create Accessible web resources
Web Page (HTML) web resources
JavaScript web resources
Image web resources
Stylesheet (XSL) web resources
Data (XML) web resources
Style Sheet (CSS) web resources
Web resource table reference
Sample: Passing multiple values to a web resource through the data parameter
Sample: Importing files as web resources
Streamline web resource development using Fiddler Auto-Responder