Replace older DevExtreme files with the latest version. You can find the new files in the DevExtreme zip archive or DevExtreme folder (C:\Program Files (x86)\DevExpress 18.1\DevExtreme\Sources\Lib by default).
If you customized the old CSS files, you should make the same changes to the new CSS files and only then use them as a replacement.
Replace the version in CDN links. Relevant links are listed in the CDN Services article.
Follow the instructions from the Add or Upgrade the Resources in an Existing Project article.
Follow the steps below to upgrade a theme created in the Theme Builder if you saved the theme's metadata:
Open the Theme Builder.
Click Import and select Import metadata from the drop-down menu.
Copy and paste the theme's metadata to the invoked window. Click Apply.
A warning is displayed that notifies you that the metadata's version does not match the Theme Builder's version. Different versions can cause issues if the Less variables used in the metadata were renamed or removed. Click Yes to continue applying the metadata.
Check that the metadata is applied, perform additional customizations if required, and save the upgraded theme.
We always do our best to minimize the impact an upgrade has on existing projects. However, it is often necessary to change our tools' UI, API, or behavior to improve them. Take the following into account to ensure that your app works after upgrading:
Refer to the breaking changes introduced in v18.1. Follow the instructions given for each change to mitigate its possible impact.
We recommend replacing depreciated APIs with their relevant counterparts because they can break your app once they are removed. Run the upgraded app and open the browser's console. A notification suggesting replacements is displayed if your code uses a deprecated API. Update your code to use the replacements instead of the deprecated API.
You can submit a ticket to our Support Center if you experience any problems migrating to the new DevExtreme version.