React Component Lifecycle methods

When a component is asked to be rendered,

• React fetches the component definition
• Instantiates the class. This is a JavaScript object, a Virtual DOM representation.
• Mounts it on the actual DOM.
• Any updates are observed and rerendering happens.

To manage the component, in the life cycle of a component, React provides three classes of interfaces for the developer.

• Mounting
• Updating
• Unmounting

The following are the methods in each class.

Mounting

Lifecycle method	one time invocation	called during initial render
componentWillMount	Yes	Yes
componentDidMount	Yes	Yes

Updating

Lifecycle method	one time invocation	called during initial render
componentWillRecieveProps	No	No
shouldComponentUpdate	No	No
componentWillUpdate	No	No
componentDidUpdate	No	No

UnMounting

Lifecycle method	one time invocation	called during initial render
componentWillUnMount	Yes	No