const data = {
a: 'a value'
}
// esnext, esm valid
const hasA = Object.hasOwnProperty.call(data, 'a'); // true
// browser, vanillajs, esnext, esm, commonjs
const hasA = data.hasOwnProperty('a'); // truevar foo = {
hasOwnProperty: function() {
return false;
},
bar: 'Here be dragons'
};
foo.hasOwnProperty('bar'); // always returns false
// Use another Object's hasOwnProperty
// and call it with 'this' set to foo
({}).hasOwnProperty.call(foo, 'bar'); // true
// It's also possible to use the hasOwnProperty property
// from the Object prototype for this purpose
Object.prototype.hasOwnProperty.call(foo, 'bar'); // true