when the decimal point is deleted, it is impossible to enter the decimal point again. How to solve this problem?
can you do the following functions similar to vue
feels that react is really too troublesome to do this.
when the decimal point is deleted, it is impossible to enter the decimal point again. How to solve this problem?
can you do the following functions similar to vue
feels that react is really too troublesome to do this.
+ event.target.value will drop the decimal point Filter, so you must remove the +
handleChange(event) {
this.setState({value: event.target.value});
} Please use + expression
class HelloMessage extends React.Component {
constructor(props) {
super(props);
this.state = {value: 1.1};
this.handleChange = this.handleChange.bind(this);
}
handleChange(event) {
this.setState({value: event.target.value});
}
render() {
var value = this.state.value;
return <div>
<input type="text" value={this.state.value} onChange={this.handleChange} />
<div>{this.state.value}</div>
<div>{Number.isNaN(Number(this.state.value)) ? '' : ''}</div>
</div>;
}
}
ReactDOM.render(
<HelloMessage />,
document.getElementById('example')
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