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    css-selector-generator
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    3.0.1 • Public • Published

    CSS Selector Generator

    JavaScript object that creates a unique CSS selector for a given DOM element.

    It also generates shorter selectors and is faster and/or more robust than many other libraries - see this comparison and select the best alternative for your use case.

    Install

    Add the library to your project via NPM or Yarn.

    npm install css-selector-generator
    yarn add css-selector-generator

    Then include it in your source code:

    import getCssSelector from 'css-selector-generator';

    How to use

    Simplest way to use it is to provide an element reference, without any options.

    <body>
    	<!-- targetElement -->
    	<div class="myElement"></div>
    </body>
    getCssSelector(targetElement);
    // ".myElement"

    Typical example is to create a selector for any element that the user clicks on:

    // track every click
    document.body.addEventListener('click', function (event) {
      // get reference to the element user clicked on
      const element = event.target;
      // get unique CSS selector for that element
      const selector = getCssSelector(element);
      // do whatever you need to do with that selector
      console.log('selector', selector);
    });

    Usage without NPM

    If you don't want to use this library with NPM, you can download it directly from the "build" folder and insert it to your HTML document directly. In this case, the library is wrapped in namespace CssSelectorGenerator. So the usage would look something like this:

    <!-- link the library -->
    <script src="build/index.js"></script>
    <script>
    	CssSelectorGenerator.getCssSelector(targtElement)
    </script

    Fallback

    getCssSelector determines the shortest CSS selector for parent -> child relationship, from the input Element until the Root Element.

    If there is no unique selector available for any of these relationships (parent -> child), a fallback of * will be used for this relationship.

    #wrapper > * > div > .text
    

    In some cases, this selector may not be unique (e.g. #wrapper > * > div > *). In this case, it will fall back to an entire chain of :nth-child selectors like:

    ":nth-child(2) > :nth-child(4) > :nth-child(1) > :nth-child(12)"
    

    Selector types

    You can choose which types of selectors do you want to use:

    <body>
    	<!-- targetElement -->
    	<div class="myElement"></div>
    </body>
    getCssSelector(targetElement, {selectors: ['class']});
    // ".myElement"
    getCssSelector(targetElement, {selectors: ['tag']});
    // "div"

    Order of selector types defines their priority:

    getCssSelector(targetElement, {selectors: ['class', 'tag']});
    // ".myElement"
    getCssSelector(targetElement, {selectors: ['tag', 'class']});
    // "div"

    Root element

    You can define root element, from which the selector will be created. If root element is not defined, document root will be used:

    <body>
    	<div class="myRootElement">
    		<!-- targetElement -->
    		<div class="myElement"></div>
    	</div>
    </body>
    getCssSelector(targetElement)
    // ".myRootElement > .myElement"
    getCssSelector(targetElement, {root: document.querySelector('.myRootElement')});
    // ".myElement"

    Blacklist

    If you want to ignore some selectors, you can put them on the blacklist. Blacklist is an array that can contain either regular expressions, or strings. In strings, you can use an asterisk (*) as a wildcard that will match any number of any characters.

    <body>
    	<!-- targetElement -->
    	<div class="firstClass secondClass"></div>
    </body>
    getCssSelector(targetElement, {blacklist: ['.firstClass']});
    // ".secondClass"
    getCssSelector(targetElement, {blacklist: ['.first*']});
    // ".secondClass"
    getCssSelector(targetElement, {blacklist: [/first/]});
    // ".secondClass"

    You can target selectors of any types using the blacklist.

    getCssSelector(
      targetElement,
      { blacklist:
          [
            // ID selector
            '#forbiddenId',
            // class selector
            '.forbiddenClass',
            // attribute selector
            '[forbidden-attribute]',
            // tag selector
            'div'
          ]
      }
    )

    Whitelist

    Same as blacklist option, but instead of ignoring matching selectors, they will be prioritised.

    <body>
    	<!-- targetElement -->
    	<div class="firstClass secondClass"></div>
    </body>
    getCssSelector(targetElement, {whitelist: ['.secondClass']});
    // ".secondClass"
    getCssSelector(targetElement, {whitelist: ['.second*']});
    // ".secondClass"
    getCssSelector(targetElement, {whitelist: [/second/]});
    // ".secondClass"

    Combine within selector

    If set to true, the generator will try to look for combinations of selectors within a single type (usually class names) to get better overall selector.

    <body>
    	<!-- targetElement -->
    	<div class="aaa bbb"></div>
    	<div class="aaa ccc"></div>
    	<div class="bbb ccc"></div>
    </body>
    getCssSelector(targetElement, {combineWithinSelector: false});
    // "body > :nth-child(1)" - in this case no single class name is unique
    getCssSelector(targetElement, {combineWithinSelector: true});
    // ".aaa.bbb"

    This option is set to true by default. It can be set to false for performance reasons.

    Combine between selectors

    If set to true, the generator will try to look for combinations of selectors between various types (e.g. tag name + class name) to get better overall selector.

    <body>
    	<!-- targetElement -->
    	<div class="aaa"></div>
    	<div class="bbb"></div>
    	<p class="aaa"></div>
    </body>
    getCssSelector(targetElement, {combineBetweenSelectors: false});
    // "body > :nth-child(1)" - in this case no single class name or tag name is unique
    getCssSelector(targetElement, {combineBetweenSelectors: true});
    // "div.aaa"

    This option is set to true by default. It can be set to false for performance reasons.

    Include tag

    This option will add tag selector type to every selector:

    <body>
    	<!-- targetElement -->
    	<div class="myElement"></div>
    </body>
    getCssSelector(targetElement, {includeTag: true});
    // "div.myElement"

    Documentation

    Table of Contents

    getCssSelector

    Generates unique CSS selector for an element.

    Parameters

    Returns string

    updateIdentifiableParent

    Utility function to make subsequent calls shorter.

    Returns {foundElement: Element, selector: string}

    css_selector_generator_options

    Type: Object

    Properties

    • selectors Array<css_selector_type>? List of selector types to use. They will be prioritised by their order.
    • whitelist Array<(RegExp | string)>? List of selectors that should be prioritised.
    • blacklist Array<(RegExp | string)>? List of selectors that should be ignored.
    • root Element? Root element inside which the selector will be generated. If not set, the document root will be used.
    • combineWithinSelector boolean? If set to true, the generator will test combinations of selectors of single type (e.g. multiple class selectors).
    • combineBetweenSelectors boolean? If set to true, the generator will try to test combinations of selectors of different types (e.g. tag + class name).
    • includeTag boolean? If set to true, all generated selectors will include the TAG part. Even if tag selector type is not included in selectors option.

    css_selector_type

    Type: ("id" | "class" | "tag" | "attribute" | "nthchild" | "nthoftype")

    Migrate from v1 to v2

    Instead of creating a class and then calling the getSelector() method, now you just call a function getCssSelector() and provide it with element reference and options:

    // v1
    const mySelectorGenerator = new CssSelectorGenerator({/* custom options */});
    mySelectorGenerator.getSelector(elementReference);
    
    // v2
    getCssSelector(elementReference, {/* custom options */});
    • Options id_blacklist, class_blacklist and attribute_blacklist are replaced with single blacklist option, which is now applied to all selector types.
    • Option attribute_whitelist is replaced with whitelist option, which is now applied to all selector types.
    • Option prefix_tag is renamed to includeTag.
    • Option quote_attribute_when_needed is removed. The attribute selectors are quoted automatically.

    Bug reports, feature requests and contact

    If you found any bugs, if you have feature requests or any questions, please, either file an issue on GitHub or send me an e-mail at riki@fczbkk.com

    License

    CSS Selector Generator is published under the MIT license.

    Keywords

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    Install

    npm i css-selector-generator

    DownloadsWeekly Downloads

    790

    Version

    3.0.1

    License

    MIT

    Unpacked Size

    241 kB

    Total Files

    58

    Last publish

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