I'm having the hardest figuring out how to this (seems so simple).
I have a Javascript Object as shown here
Output of console.log(data):
{"prevExists":false,"pubKey":"b5","ID":"5f1"}
I'm trying to access the different key value pairs.
When I try the expected methods, I get back undefined.
I have tried:
var pubKey = "pubKey";
data.pubKey
data[pubkey];
data["pubKey"];
I know I'm missing something really obvious here.
You have several ways of accessing keys, depending on which keys you're talking about.
In your example, any of those would work:
var data = {
"prevExists":false,
"pubKey":"b5",
"ID":"5f1"
};
// Access all keys of enumerable string-keyed properties
Object.keys(data).forEach((key) => console.log(key,data[key]));
// Access all keys of enumerable and non-enumerable string-keyed properties
Object.getOwnPropertyNames(data).forEach((key) => console.log(key,data[key]));
// Access all keys of enumerable string-keyed properties of your object, its prototype, and all the prototype chain...
for (let key in data)
console.log(key,data[key]);
If you want to have a better understanding of what is an object's property, you can have a look at this recent answer I wrote on the topic.
You can use Object.keys and a foreach loop to access the properties on the object.
var data = {"prevExists":false,"key":"b5","ID":"5f1"};
Object.keys(data).forEach(function(key) {
console.log('key - ' + key + ' :: value - ' + data[key]);
});
First you need to create a reference to your object. Like this:
var myObj = { "prevExists": false, "key": "b5", "ID": "5f1" };
Then, you can access the elements using their keys:
console.log(myObj["prevExists"]);
Console exit:
false
Good luck!
myArray to data, because it's definitely not an array ;)Use the Object.keys method
var data = {"prevExists":false,"pubKey":"b5","ID":"5f1"}
console.log(Object.keys(data));The
Object.keys()method returns an array of a given object's own enumerable properties, in the same order as that provided by afor...inloop (the difference being that a for-in loop enumerates properties in the prototype chain as well).
You are confusing yourself with the line var pubKey="pubKey". There are 2 ways to access object parameters:
const data = {"prevExists":false,"pubKey":"b5","ID":"5f1"};
// var pubKey = "pubKey"; This line is not needed
1) data.pubKey
If you use the dot operator (.), then you reference it with the key name.
2) data["pubKey"];
If you use brackets ([]), then you use the string that matches the key.
If you add the line:
const pubKey = "pubKey";
, then data[pubKey] will also work, because it evaluates to data["pubKey"]
data? All 3 should have worked indeed.