Truncate.js

Fast, intelligent Javascript text truncation

Usage

Truncate.js currently depends on jQuery. There are two ways to use Truncate.js:

As a jQuery plugin

// Initialize and truncate.
$('#truncate_me').truncate({
  lines: 2
});

// Update the HTML and truncate.
$('#truncate_me').truncate('update', 'new html to truncate');

// Undo the truncation.
$('#truncate_me').truncate('expand');

// Redo the truncation (uses cached HTML).
$('#truncate_me').truncate('collapse');

// Update options.
$('#truncate_me').truncate('config', { lines : 3 });

As a vanilla Javascript object

// Initialize and truncate.
var truncated = new Truncate(document.getElementById('#truncate_me'), {
  lines: 2
});

// Update the HTML and truncate.
truncated.update('new html to truncate');

// Undo the truncation.
truncated.expand();

// Redo the truncation (uses cached HTML).
truncated.collapse();

// Update options.
truncated.config({ lines : 3 });

// Check if content is truncated. (not supported as a jQuery plugin)
var isTruncated = truncated.isTruncated;

// Check if content is collapsed. (not supported as a jQuery plugin)
var isCollapsed = truncated.isCollapsed

Options

• lineHeight: The text line height (in px). default: "auto"
• lines: The number of line maximum. default: 1
• ellipsis: Text content to add at the truncation point. default: …
• showMore: HTML to insert at the truncation point. Useful for a "Show More" button. default: ""
• showLess: HTML to insert when .expand() is called. Useful for a "Show Less" button. default: ""
• position: Position of the truncation. Possible values: start, middle, end. default: "end"
• maxHeight: Truncate the content to fit in the specified height (in px).

Caveats

Truncate.js does it's best to intelligently truncate through HTML. However, there are a few cases where it fails, mostly because the text height cannot be easily calculated.

• truncating a node with floating element
• truncating a node with descendant elements that have padding
• truncating a node with text of varying line heights

The truncate position is also very difficult when set to middle and with nested elements.

See demo/demo.html for examples of what works and what doesn't.

Build

You need gulp to build the library:

$ npm install
$ npm run build

The output is in the dist folder

Development

It's very simple, hack on the code, ensure the lint and tests pass and submit a pull request. Rinse and repeat.

To install the developer packages you'll need node and npm installed on your machine. Then run:

$ npm install
$ npm run build

Or you can use Gulp directly:

$ npm install --global gulp-cli
$ npm install
$ gulp build

To run the linter:

$ npm run lint

Testing

To run the test suite:

$ npm run test

Libraries

• Mocha - Test runner, we use the bdd style.
• Chai - Assertion library, we use assert style.
• Gulp - Builder

License

Available under the MIT license. See LICENSE file for details.