componentWillMoumt is deprecated
this article is very usefull

componentWillMount is deprecated. Please update the article. Thanks

thanku so i want this like ...so agin thanku

Thanks for this!

set the initial state in the constructor

I think the constructor is called first then the other cycles. Right?

yes..Actually the author should correct the post because the sequence is
1. constructor
2. ComponentWillMount
3. Render
4. ComponentDidMount
5. Render

Try this code for proof:-
----------------------------

import React, { Component } from 'react';

class App extends Component {
componentWillMount(){
alert('ComponentWillMount');
console.log('First this called');
}
constructor(props){
alert('before super');
super(props);
alert(' before state constructor');
this.state = {
data: 'Jordan Belfort'
}
alert('after state constructor');
}

getData(){
setTimeout(() => {
console.log('Our data is fetched');
this.setState({
data: 'Hello WallStreet'
})
}, 1000)
}

componentDidMount(){
alert('ComponentDidMount');
this.getData();
}

render() {
alert('render');
return(
<div>
{this.state.data}
</div>
)
}
}

export default App;

Nice, Thanks for the sharing article about this.