How to access custom attributes from event object in React?

Question

React is able to render custom attributes as described at http://facebook.github.io/react/docs/jsx-gotchas.html:

If you want to use a custom attribut

Answer 1

// Method inside the component
userClick(event){
 let tag = event.currentTarget.dataset.tag;
 console.log(tag); // should return Tagvalue
}
// when render element
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