dojo.hasClass

Project owner:Eugene Lazutkin since:V0.9

Contents

• dojo.hasClass
  • Usage
  • See also

Returns a boolean depending on whether or not a node has a passed class string.

Since Dojo 1.7, dojo.hasClass is exposed via the contains() method of the dojo/dom-class module. An alias is kept in dojo/_base/html for backward-compatibility.

Usage

The function takes two arguments:

1. A DOM node or its node id (as a string).
2. A CSS class name as a string.

It returns true if the node has the class, and false otherwise.

Dojo 1.7+ (AMD)

When using AMD format in a fully baseless application, contains is accessed from the dojo/dom-class module.

require(["dojo/dom-class"], function(domClass){
    // Do something if a node with id="someNode" has class="aSillyClassName" present
    if(domClass.contains("someNode", "aSillyClassName")){ ... }
});

require(["dojo/dom-class"], function(domClass){ // Do something if a node with id="someNode" has class="aSillyClassName" present if(domClass.contains("someNode", "aSillyClassName")){ ... } });

Alternatively, you can load dojo base in AMD style and continue using dojo.hasClass in the define or require callback:

require(["dojo"], function(dojo){
    // Do something if a node with id="someNode" has class="aSillyClassName" present
    if(dojo.hasClass("someNode", "aSillyClassName")){ ... }
});

require(["dojo"], function(dojo){ // Do something if a node with id="someNode" has class="aSillyClassName" present if(dojo.hasClass("someNode", "aSillyClassName")){ ... } });

Dojo < 1.7

// Do something if a node with id="someNode" has class="aSillyClassName" present
if(dojo.hasClass("someNode", "aSillyClassName")){ ... }

// Do something if a node with id="someNode" has class="aSillyClassName" present if(dojo.hasClass("someNode", "aSillyClassName")){ ... }

Consider the following html:

<div id="bam" class="foo bar baz"></div>
<div class="something else"></div>

<div id="bam" class="foo bar baz"></div> <div class="something else"></div>

Using dojo.hasClass to find if the node id="bam" has class="foo":

// Dojo 1.7+ (AMD)
require(["dojo/dom-class"], function(domClass){
  if(domClass.contains("bam", "foo")){
    /* it does */
  }
});

// Dojo < 1.7
if(dojo.hasClass("bam", "foo")){
  /* it does */
}

// Dojo 1.7+ (AMD) require(["dojo/dom-class"], function(domClass){ if(domClass.contains("bam", "foo")){ /* it does */ } }); // Dojo < 1.7 if(dojo.hasClass("bam", "foo")){ /* it does */ }

Using dojo.query to find a node and check if it has a class:

// Dojo 1.7+ (AMD)
require(["dojo/dom-class", "dojo/query"], function(domClass, query){
   query(".something").forEach(function(node){
     if(domClass.contains(node, "else"){
        /* it does */
     }
  });
});

// Dojo < 1.7
dojo.query(".something").forEach(function(node){
   if(dojo.hasClass(node, "else"){
      /* it does */
   }
});

// Dojo 1.7+ (AMD) require(["dojo/dom-class", "dojo/query"], function(domClass, query){ query(".something").forEach(function(node){ if(domClass.contains(node, "else"){ /* it does */ } }); }); // Dojo < 1.7 dojo.query(".something").forEach(function(node){ if(dojo.hasClass(node, "else"){ /* it does */ } });

Note: You do not need to explicitly check for dojo.hasClass before adding or removing a class with dojo.addClass or dojo.removeClass, they do it for you.

See also

• dojo.addClass
• dojo.removeClass
• dojo.toggleClass

Table of Contents

• dojo.hasClass
  • Usage
    • Dojo 1.7+ (AMD)
    • Dojo < 1.7
  • See also