```
render () {
  <input type="number" value={this.props.value} />
}
```

for example, when the original value is '.98', we need format it to '0.98'. but it is not  take effect。

```javascript
class Test extends React.Component {
 state = {
    value: '.98',
  }
 changeValue = () => {
    alert(0.98);
    this.setState({
      value: '0.98',
    });
  }

 render() {
    return <div>
      <input type="number" value={this.state.value} />
      <button onClick={this.changeValue}>changeValue</button>
    </div>;
  }
}

ReactDOM.render(<Test />, mountNode);
```



render() {
        return <input defaultValue="0" />;
      }
    }
    var component = ReactTestUtils.renderIntoDocument(<Test />);
    var node = ReactDOM.findDOMNode(component);
    Object.defineProperty(node, 'defaultValue', {
      get() {
        return '0';
      },
      set(value) {