如何从Reactjs组件的状态对象中删除属性

问题描述

如果我有一个在状态下设置了属性的react组件:

If I have a react component that had a property set on it's state:

onClick() {
    this.setState({ foo: 'bar' });
}

是否可以从Object.keys(this.state)中删除"foo"?

replaceState 方法看起来像是显而易见的方法但此后就被贬值了.

The replaceState method looks like the obvious method to try but it's since been depreciated.

推荐答案

您可以将foo设置为undefined，就像这样

You can set foo to undefined, like so

var Hello = React.createClass({
    getInitialState: function () {
        return {
            foo: 10,
            bar: 10
        }
    },

    handleClick: function () {
        this.setState({ foo: undefined });
    },

    render: function() {
        return (
            <div>
                <div onClick={ this.handleClick.bind(this) }>Remove foo</div>
                <div>Foo { this.state.foo }</div>
                <div>Bar { this.state.bar }</div>
            </div>
        );
    }
});

Example

更新

先前的解决方案只是从state中删除foo和 key 技能的值，如果您需要从state中完全删除密钥，则可能的解决方案之一是有一个父级 key ，就像这样

The previous solution just remove value from foo and key skill exists in state, if you need completely remove key from state, one of possible solution can be setState with one parent key, like so

var Hello = React.createClass({
  getInitialState: function () {
    return {
      data: {
        foo: 10,
        bar: 10
      }
    }
  },

  handleClick: function () {
    const state = {
      data: _.omit(this.state.data, 'foo')
    };

    this.setState(state, () => {
      console.log(this.state);
    });
  },

  render: function() {
    return (
      <div>
        <div onClick={ this.handleClick }>Remove foo</div>
        <div>Foo { this.state.data.foo }</div>
        <div>Bar { this.state.data.bar }</div>
      </div>
    );
  }
});

ReactDOM.render(<Hello />, document.getElementById('container'))

<script src="https://cdn.jsdelivr.net/lodash/4.17.4/lodash.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<div id="container"></div>

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