React's setState method with prevState argument

Question

I\'m new to React, just have a question on setState method. Let\'s say we have a component:

class MyApp extends React.Component {

  state = {
    count: 3
          


        

Answer 1

here iseveryone know just state:prevstate.counter+1.. we can also do this with state:this.state.counter+1. This is not the way i think to use prevstate. i have problem in array when i push into existing state it allow me but second time it prevent changes