So überprüfen Sie, ob das Objekt einen Schlüssel -JavaScript hat
myObj.hasOwnProperty('key') // it checks object for particular key and not on prototype
Proud Pony
myObj.hasOwnProperty('key') // it checks object for particular key and not on prototype
if ('key' in myObj)
// better
if (!myObj.hasOwnProperty('key'))
if ('key' in myObj)
Object.prototype.hasOwnProperty()