There is another option and this works if there are multiple items in the list of objects: copy the object using this.state.Obj to a variable (say temp), use filter() method to traverse through the object and grab the particular element you want to change into one object(name it updateObj) and the remaining list of object into another object(name this as restObj). Now edit the contents of object you want to update creating a new item (say newItem). Then call this.setUpdate() and use spread operators to assing new list of objects to the parent object.

this.state = {someProperty: { flag:true, }}


var temp=[...this.state.someProperty]
var restObj = temp.filter((item) => item.flag !== true);
var updateObj = temp.filter((item) => item.flag === true);

var newItem = {
  flag: false
};
this.setState({ someProperty: [...restObj, newItem] });

有很多库可以提供帮助。例如，使用immutability-helper:

import update from 'immutability-helper';

const newState = update(this.state, {
  someProperty: {flag: {$set: false}},
};
this.setState(newState);

使用lodash/fp设置:

import {set} from 'lodash/fp';

const newState = set(["someProperty", "flag"], false, this.state);

使用lodash/fp合并:

import {merge} from 'lodash/fp';

const newState = merge(this.state, {
  someProperty: {flag: false},
});

下面是一个完整的例子，使用嵌套状态(一层)和这个答案中的解决方案，对于一个实现为类的组件:

class CaveEditModal extends React.Component {

  // ...

  constructor(props, context) {
    super(props);
    this.state = {

      tabValue: '1',
      isModalOpen: this.props.isModalOpen,

      // ...
      caveData: {
        latitude: 1,
        longitude: 2      
      }
    };

    // ... 

    const updateNestedFieldEvent = fullKey => ev => { 
      
      var [parentProperty, _key] = fullKey.split(".", 2);

      this.setState({[parentProperty]: { ...this.state[parentProperty], [_key]: ev.target.value} });
    };
    // ...

    this.handleLatitudeChange = updateNestedFieldEvent('caveData.latitude');
    this.handleLongitudeChange = updateNestedFieldEvent('caveData.longitude');
  }

  render () {    
    return (
      <div>
         <TextField id="latitude" label="Latitude" type="number" value={this.state.caveData.latitude} onChange={this.handleLatitudeChange} />
         <TextField id="longitude" label="Longitude" type="number" value={this.state.caveData.longitude} onChange={this.handleLongitudeChange} />
         <span>lat={this.state.caveData.latitude} long={this.state.caveData.longitude}</span>
      </div>
    );
  };

}

注意，状态更新器函数updateNestedFieldEvent只适用于一层嵌套对象，比如a.b，而不是a.b.c。

对于在2022年读书的人来说:

    constructor(props) {
        super(props);
        this.state = {
            someProperty: {
                flag: true
            }
            otherValues: '',
            errors: {}
        };

        this.handleInputChange = this.handleInputChange.bind(this);
    }

    handleInputChange(event) {
        const target = event.target;
        const value = target.type === 'checkbox' ? target.checked : target.value;
        const name = target.name;
        const someProperty = { ...this.state.someProperty };
        someProperty[name] = value;

        this.setState({
            someProperty: someProperty
        });
    }
    .......

这是第一个答案的变体，不需要任何额外的包、库或特殊函数。

state = {
  someProperty: {
    flag: 'string'
  }
}

handleChange = (value) => {
  const newState = {...this.state.someProperty, flag: value}
  this.setState({ someProperty: newState })
}

为了设置特定嵌套字段的状态，您已经设置了整个对象。为此，我创建了一个变量newState，并首先使用ES2015扩展操作符将当前状态的内容扩散到该变量中。然后，我用新值替换了this.state.flag的值(因为我在将当前状态扩展到对象后设置了flag: value，所以当前状态下的flag字段将被覆盖)。然后，我简单地将someProperty的状态设置为newState对象。

const newState = Object.assign({}, this.state);
newState.property.nestedProperty = "new value";
this.setState(newState);