component will mount react hooks code example

Example 1: replace componentwillmount with hooks

useEffect(() => {
	//will be called on every load
})

useEffect(() => {
	//will be called on component mount
  window.addEventListener('mousemove', () => {});

  // returned function will be called on component unmount 
  return () => {
    window.removeEventListener('mousemove', () => {})
  }
}, []) // <---- empty array at end will cause to only run on first load

Example 2: component did mount in hooks

For componentDidMount
useEffect(() => {
  // Your code here
}, []);

For componentDidUpdate
useEffect(() => {
  // Your code here
}, [yourDependency]);

For componentWillUnmount
useEffect(() => {
  // componentWillUnmount
  return () => {
     // Your code here
  }
}, [yourDependency]);

Example 3: componentwillunmount hooks

useEffect(() => {
  window.addEventListener('mousemove', () => {});

  // returned function will be called on component unmount 
  return () => {
    window.removeEventListener('mousemove', () => {})
  }
}, [])

Example 4: react hook will mount

const useComponentWillMount = (func: (params?: any) => any) => useMemo(func, []);

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Misc Example