React Handling Event

React Event are in camelCase

<button onClick={handleClick}>
  Action
</button>

Use preventDefault instead of return false

function handleClick(e) {
  e.preventDefault();
}

Bind this to use it in the callback

constructor(props) {
  super(props);
  this.handleClick = this.handleClick.bind(this);
}

Pass data to callback

<button onClick={(e) => this.deleteItem(id, e)}>Delete item</button>
<button onClick={this.deleteItem.bind(this, id)}>Delete item</button>