Reactjs setState() with a dynamic key name?

trad picture trad · Mar 26, 2015 · Viewed 169.6k times · Source

EDIT: this is a duplicate, see here

I can't find any examples of using a dynamic key name when setting the state. This is what I want to do:

inputChangeHandler : function (event) {
    this.setState( { event.target.id  : event.target.value } );
},

where event.target.id is used as the state key to be updated. Is this not possible in React?

Answer

trad picture trad · Mar 26, 2015

Thanks to @Cory's hint, i used this:

inputChangeHandler : function (event) {
    var stateObject = function() {
      returnObj = {};
      returnObj[this.target.id] = this.target.value;
         return returnObj;
    }.bind(event)();

    this.setState( stateObject );    
},

If using ES6 or the Babel transpiler to transform your JSX code, you can accomplish this with computed property names, too:

inputChangeHandler : function (event) {
    this.setState({ [event.target.id]: event.target.value });
    // alternatively using template strings for strings
    // this.setState({ [`key${event.target.id}`]: event.target.value });
}