HTML

CLion brings powerful support for HTML that includes syntax and error highlighting, formatting according to the code style, structure validation, code completion, on-the-fly preview during a debugging session (Live Edit) or in the dedicated preview tab in the code editor, and much more.

HTML specification is configurable with the Default HTML language level preference on the Languages and Frameworks | Schemas and DTDs page of the IDE settings Ctrl+Alt+S. By default, specification HTML 5.0 from W3C is assumed.

Creating an HTML file

From the main menu, select File | New, and then select HTML File from the list. CLion creates a stub file based on the HTML file template and opens it in the editor.

Creating references in an HTML file

Inside a <script>, <link>, or <img> tag, CLion suggests completion for the path to the file you are referencing.

Alternatively, in the Project tool window, select the JavaScript, CSS, or image file you want to reference and drag it into the HTML file. CLion generates the <script>, <link>, or <img> tags inside <head>. For <img> tags, CLion also generates the width and height attributes.

Generating a reference by dragging and dropping

Wrapping a code fragment in a tag

Select the code fragment to wrap and press Ctrl+Alt+T or select Code | Surround With from the main menu.
From the list, select Wrap with Tag. CLion encloses the selection in a pair of brackets (<> and </>).
Type the tag inside the opening brackets <>. CLion automatically fills in the tag in the closing brackets </>.

Learn more from Code generation.

Documentation look-up

For most HTML tags and attributes CLion can show you a summary from the corresponding MDN article. This summary is displayed in the Documentation popup which also shows the deprecation status of a tag or an attribute and information on its compatibility with various browsers.

If the tag or the attribute is available in all versions of browsers, CLion does not show any information about its compatibility.

HTML quick documentation: attribute is available in all versions of browsers

Otherwise, the Documentation popup also lists the browsers and their versions that support the tag or the attribute.

HTML quick documentation: compatible browsers are listed

If the tag or the attribute is deprecated, the popup also informs you about this status.

HTML quick documentation: status Deprecated for <big> tag

View documentation for a tag or an attribute

Position the caret at the tag or the attribute and press Ctrl+Q or select View | Quick Documentation Lookup from the main menu.
When you hover the mouse pointer over a tag or an attribute, CLion immediately displays the reference for it in the Documentation popup.
You can turn off this behavior or configure the popup to appear faster or slower, see Configuring the behavior of Documentation popup below.

Configure the behavior of Documentation popup

To turn off showing documentation automatically, open the Settings/Preferences dialog Ctrl+Alt+S, go to Editor | Code Editing, and clear the Show quick documentation on mouse move checkbox.
To have the Documentation popup shown faster or slower, open the Settings/Preferences dialog Ctrl+Alt+S, go to Editor | General | Code Completion, then select the Show the documentation popup checkbox and specify the delay time.

Open the MDN documentation for tags and attributes in the browser

In the Documentation popup Ctrl+Q, click the link at the bottom.
Press Shift+F1 or select View | External Documentation from the main menu.

Previewing output of an HTML file

You can open the output of your HTML code in the built-in CLion preview or externally, in a browser of your choice.

CLion opens the built-in preview in an editor tab, saves any changes you make to an HTML file or to the linked CSS and JavaScript files, and reloads the preview automatically. This makes your work faster as you no longer need to switch to the browser and refresh the pages.

Open the CLion built-in preview

From the main menu, select View | Open in Browser, and then select Built-in Preview from the list.
Alternatively, hover your mouse pointer over the code to show the browser icons popup, and click .

To make sure your HTML code is rendered properly in production environment, preview HTML files in specific browsers.

Preview an HTML file in a browser

From the main menu, select View | Open in Browser, and then select the desired browser from the list.
To open the CLion default browser, select Default.
Alternatively, hover your mouse pointer over the code to show the browser icons popup, and click the icon that indicates the desired browser:
If you have only one browser configured, just press Alt+F2.

Configure the browser icons in the popup

Open the Settings/Preferences dialog Ctrl+Alt+S and go to Tools | Web Browsers.
To hide some of the icons, clear the Active checkboxes for the unnecessary browsers.
To hide the whole popup, clear the For HTML files checkbox.

Viewing HTML source code of a web page in the editor

Press Ctrl+Shift+A and select Open Source Code from URL... from the list.
In the Open URL dialog that opens, type the URL address of the web page or choose a previously opened URL from the list.

Viewing embedded images

CLion offers several ways to view images embedded in an HTML file. You can use navigation to source, open an image in an external graphical editor, or preview images on-the-fly.

View images in CLion

Select the image file in the Project tool window and press F4.
Alternatively, position the caret at the reference to the image in the editor and press Ctrl+B
To preview an image in a popup instead of in a separate tab, select the reference to it and press Ctrl+Shift+I

View images in an external editor

Select the image file in the Project tool window, and select Jump to external editor or press Ctrl+Alt+F4.
CLion opens the image in the editor that is used in your OS by default. You can configure another image editor in which the IDE will open files.

Change the default external editor

Right-click an image in the editor and select Edit Path to External Editor from the context menu.
You can also press Ctrl+Shift+A and type Edit Path to External Editor.
In the Path to External Editor dialog, specify the path to the application in which you want to open images and click Save.

Extracting an include file

You can extract a fragment of HTML code into a separate include file. Entire JavaScript code blocks inside a <script> tags can be extracted as well. CLion also suggests adding references instead of duplicates of the selected fragment.

In the editor, select the code block to be extracted and choose Refactor | Extract | Extract Include File from the main menu or from the context menu of the selection.
In the Extract Include File dialog that opens, specify the name of the include file without the extension and the directory to store it in. You can accept the predefined directory or select another one.
Click OK, when ready. CLion extracts the selected source code into the specified file in the target directory and generates the corresponding reference in the source file.

Configuring syntax highlighting

You can configure HTML-aware syntax highlighting according to your preferences and habits.

In the Settings/Preferences dialog Ctrl+Alt+S, go to Editor | Color Scheme | HTML.
Select the color scheme, accept the highlighting settings inherited from defaults or customize them as described in Colors and fonts.

Last modified: 16 July 2021