How do I setState for nested object?

let newAccess = Object.assign({}, this.state.access);
newAccess.hospital_id = 1;
this.setState({access: newAccess});

My preferred way of doing this now is as simple as:

let newAccess = this.state.access;
newAccess.hospital_id = 1;
setState({access: newAccess});

Slightly simpler than the current accepted answer.

EDIT (based on the question from @SILENT )

It looks like this is actually a potentially dangerous method. Further reading here React: A (very brief) talk about immutability.

Looks like a better way to do this would be:

let newAccess = Object.assign({}, this.state.access, {hospital_id:1});
this.setState({access: newAccess});

You have a few options:

1. With ECMA6, you can use the Object spread proposal (...) to create copies of objects with updated properties.

   this.setState({
     access: {
       ...this.state.access,
       hospital_id: 1,
     },
   });
   

2. You can use the native assign function on the Object (Object.assign())

   this.setState({
     access: Object.assign({}, this.state.access, {
       hospital_id: 1,
     }),
   });
   

3. Or for the shortest version and atomic update:

    this.setState(({access}) => ({access: {
      ...access,
      hospital_id: 1,
    }});
   

4. And one more option is the updates addon:

   var update = require('react-addons-update');
   // per React docs 
   // https://reactjs.org/docs/update.html 
   // , you may want to change this to 
   // import update from 'immutability-helper';
   this.setState({
     access: update(this.state.access, {
       hospital_id: {$set: 1},
     })
   });
   

I would recommend using the first one.