The typical way of creating a Javascript object is the following:
var map = new Object();
map[myKey1] = myObj1;
map[myKey2] = myObj2;
I need to create such a map where both keys and values are Strings. I have a large but static set of pairs to add to the map.
Is there any way to perform something like this in Javascript:
var map = { { "aaa", "rrr" }, { "bbb", "ppp" } ... };
or do I have to perform something like this for each entry:
map["aaa"]="rrr";
map["bbb"]="ppp";
...
Basically, remaining Javascript code will loop over this map and extract values according to criterias known 'at runtime'. If there is a better data structure for this looping job, I am interested too. My objective is to minimize code.
This question is related to
javascript
object-literal
static-initialization
The syntax you wrote as first is not valid. You can achieve something using the follow:
var map = {"aaa": "rrr", "bbb": "ppp" /* etc */ };
It works fine with the object literal notation:
var map = { key : { "aaa", "rrr" },
key2: { "bbb", "ppp" } // trailing comma leads to syntax error in IE!
}
Btw, the common way to instantiate arrays
var array = [];
// directly with values:
var array = [ "val1", "val2", 3 /*numbers may be unquoted*/, 5, "val5" ];
and objects
var object = {};
Also you can do either:
obj.property // this is prefered but you can also do
obj["property"] // this is the way to go when you have the keyname stored in a var
var key = "property";
obj[key] // is the same like obj.property
In ES2015 a.k.a ES6 version of JavaScript, a new datatype called Map
is introduced.
let map = new Map([["key1", "value1"], ["key2", "value2"]]);
map.get("key1"); // => value1
check this reference for more info.
Give this a try:
var map = {"aaa": "rrr", "bbb": "ppp"};
Source: Stackoverflow.com