TypeError：无法读取未定义的属性“ stateUpdate”（哪个函数）/将数据从父级传递到子级

Question

I'm having an issue of passing a function from parent to child component in react js .

I have tried to pass the vale to the component as props but it is showing the type error as defined in the question. i am not able to figure out why is it happening.

Is it because of mapping, if so how to solve it because mapping is important.

Parent Component:

stateUpdate(){
      alert("hi");
    }
    render() {

          const tabList =  this.state.productMapData.map(function(object, i){
            return <TableList obj={object} ids = {productRegistrationArrId} key={i} 

Error here:

 parent= {this.stateUpdate.bind(this)}></TableList>
              })
        return (
          <div> 
            <div style={{ marginTop: 10, marginLeft: "10%" }}>
            <Link to="/api/productregistration" className="btn btn-info" onClick = {this.onDeleteDb} >
                Back to List
            </Link>

Child Component:

onUpdate(){
        this.props.parent;    
    }

Answer 1

In parent stateUpdate function declare using arrow function then you may not get this issue. I have mentioned sample code below please find it

stateUpdate =()=> {
  alert("hi");
}

and in child component in update function you have to call parent function like

onUpdate=()=>{
        this.props.parent();  
       // here you have to change parent to parent()
    }