The object
type refers to a compound value where you can set properties (named locations) that each hold their own values of any type.
var obj = {
a: "hello world", // property
b: 42,
c: true
};
obj.a; // "hello world", accessed with doted notation
obj.b; // 42
obj.c; // true
obj["a"]; // "hello world", accessed with bracket notation
obj["b"]; // 42
obj["c"]; // true
Bracket notation is also useful if you want to access a property/key but the name is stored in another variable, such as:
var obj = {
a: "hello world",
b: 42
};
var b = "a";
obj[b]; // "hello world"
obj["b"]; // 42
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