#
Working with Objects
Enmap is a great way to store structured data, and offers a few helper features that directly affect both objects and arrays.
Let's assume for a moment that we want to store the following data structure in Enmap:
const myStructure = {
first: "blah",
second: "foo",
changeme: "initial",
isCool: false
sub: {
yay: true,
thing: "amagig"
}
}
This structure has 5 "properties": first
, second
, changeme
, isCool
, sub
. The sub
property has 2 properties of its own, yay
and thing
.
To store this structure in Enmap, you can use a variable, or just straight-up write the object:
myEnmap.set("someObject", myStructure);
// Or directly the object
myEnmap.set("someObject", {first: "blah", ...});
// Works with arrays, too!
myEnmap.set("someArray", ["one", "two", "three"]);
Note: All further methods require the value to be an object. If you attempt to get, set, modify or remove using the below methods and your value isn't an object, Enmap will throw an error.
#
Getting properties
Retrieving a specific property from an object is done through the get()
method, by specifying both the key and the "path" to the property you want.
The exact method is <Enmap>.get(key, path)
.
const second = myEnmap.get("someObject", "second");
// returns "foo"
const thing = myEnmap.get("someObject", "sub.yay");
// returns true
// The path can be dynamic, too:
const propToGet = "thing";
const blah = myEnmap.get("someObject", `sub.${propToGet}`);
#
Checking if a property exists
You can also check if a specific property exists or not. This is done through the has
method, with a key, and path to the property:
myEnmap.has("someObject", "sub.thing"); // returns true
myEnmap.has("someObject", "heck"); // returns false.
#
Modifying Properties
There are a few various ways to modify properties of both Objects and Arrays. The very basic way to set a property on an object or array is through .set(key, value, path)
like the following examples:
// Set an object property
myEnmap.set("someObject", "newThing", "sub.blah");
// Set an array property
myEnmap.set("someArray", "four", 3);
As you can see, setProp() and getProp() work on the same concept that the path can be as complex as you want.
Arrays have additional helper methods, you can see them here.