indexof key value javascript code example

Example 1: indexOf by object key

var index = peoples.findIndex(p => p.attr1 == "john")

Example 2: index of value in array

// for dictionary case use findIndex 
var imageList = [
   {value: 100},
   {value: 200},
   {value: 300},
   {value: 400},
   {value: 500}
];
var index = imageList.findIndex(img => img.value === 200);