README.md

React

Basic

React.renderROM()

ReactDOM.render(

);

React.createElement()

Component life-cycle

• componentWillMount()
  • render() 직전에 불림.
• componentDidmount()
  • component가 DOM 에 mount 직후 => this 사용 가능함. (this.state)
  • Preparation for API usage.
• componentWillReceiveProps()
  • props update 시
  • nextProps 와 this.props 비교.
• componentDidUpdate()
  • component re-render 한 직후에 불림.

Counter example

Redux: Write a Counter with Redux | Learn freeCodeCamp

const INCREMENT = "INCREMENT";
const DECREMENT = "DECREMENT";

const counterReducer = (state = 0, action) => {
  switch (action.type) {
    case INCREMENT:
      return state + 1;
    case DECREMENT:
      return state - 1;
    default:
      return state;
  }
};

const incAction = () => {
  return {
    type: INCREMENT
  };
};

const decAction = () => {
  return {
    type: DECREMENT
  };
};

const store = Redux.createStore(counterReducer);