handling state in class components reactjs ijnterview questions
class ClassRoom extends React.Component{
constructor(props){
super(props);
this.state = {studentsCount : 0};
this.addStudent = this.addStudent.bind(this);
}
addStudent(){
this.setState((prevState)=>{
return {studentsCount: prevState.studentsCount++}
});
}
render(){
return(
<div>
<p>Number of students in class room: {this.state.studentsCount}</p>
<button onClick={this.addStudent}>Add Student</button>
</div>
)
}
}