javascript - react.js dynamically grabbing object resulting in undefined -


i learning react.js. have object literal , trying dynamically select object within object based upon chosen select input. getting undefined, however. have tried both dot , bracket notation. grabbing value of selected option , storing within variable. ideas?

here object: 

var horolist = { aries: {     title: "jerkface", }, cancer: {     title: "cancerous", }, gemini : {     title: "goofball" } } ;

here of jsx within render method:

                    <select name="pick-sign" onchange={this.handlechange}>                         <option></option>                         <option value="aries" >aries</option>                         <option value="cancer" >cancer</option>                         <option value="gemini" >gemini</option>                         <option value="taurus" >taurus</option>                     </select>

and here handle change method:

        handlechange: function(e) {         var selectedhoro = e.target.value;         console.log(selectedhoro); //outputs: aries         console.log(horolist); //outputs: object {aries: object, cancer: object, gemini: object}         console.log(horolist.aries); //ouputs: object {title: "jerkface"}         console.log(horolist['selectedhoro']); //outputs: undefined         // this.setstate({         //  horos: horolist.selectedhoro         // });     },

if change line:

console.log(horolist['selectedhoro']); //outputs: undefined

to:

console.log(horolist[selectedhoro]);

you should expected output. when use horolist['selectedhoro'], literal string value selectedhoro used horolist.selectedhoro. when use horolist[selectedhoro], selectedhoro variable , it's value used determine property name want resolve resolve horolist.aeries (when selectedhoro === aeries).


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