I have a main page component in react whose render function looks like this
const MainPage = () => {
return (
<>
<Component1 />
<Component2 />
</>
)
}
And Component has some inputs
const Component1 = () => {
const [val1, setVal1] = React.useState("");
const [val2, setVal2] = React.useState("");
return (
<>
<input type="text" value={val1} onChange={setVal1} />
<input type="text" value={val2} onChange={setVal2} />
</>
)
}
My question is how to get values val1 and val2 in the MainPage component? Thanks in advance
CodePudding user response:
use Redux or Context API in your React Project. Btw you can call the function to get the children component variables value.
Example React using Class
class Parent extends Component {
constructor() {
this.state = {
value: ''
};
}
//...
handleChangeValue = e => this.setState({value: e.target.value});
//...
render() {
return (
<Child
value={this.state.value}
onChangeValue={this.handleChangeValue}
/>
);
}
}
class Child extends Component {
//...
render() {
return (
<input
type="text"
value={this.props.value}
onChange={this.props.onChangeValue}
/>
);
}
}
CodePudding user response:
You can't.
React is based on Unidirectional Data Flow
So to solve your problem you must define an event that will be called from the children.
const MainPage = () => {
const [val1, setVal1] = React.useState("");
const [val2, setVal2] = React.useState("");
return (
<>
<Component1 val1={val1} onChange1={setVal1} val2={val2} onChange2={setVal2} />
<Component2 />
</>
)
}
And Component1
const Component1 = ({val1, onChange1, val2, onChange2}) => {
return (
<>
<input type="text" value={val1} onChange={onChange1} />
<input type="text" value={val2} onChange={onChange2} />
/>
</>
)
}