Question

I have seen the following code in a website…
what does this mean?.Can i declare variables in the format variableName : value instead of variableName = value.

     if (!window.Node){
       var Node =
      {
        ELEMENT_NODE                :  1,
        ATTRIBUTE_NODE              :  2,
        TEXT_NODE                   :  3,
        CDATA_SECTION_NODE          :  4,
        ENTITY_REFERENCE_NODE       :  5,
        ENTITY_NODE                 :  6,
        PROCESSING_INSTRUCTION_NODE :  7,
        COMMENT_NODE                :  8,
        DOCUMENT_NODE               :  9,
        DOCUMENT_TYPE_NODE          : 10,
        DOCUMENT_FRAGMENT_NODE      : 11,
        NOTATION_NODE               : 12
    };
}

Answer 1

Those are object properties in an object litteral.

Empty object litteral:

var obj = {};

With properties:

var obj = {
    foo: "bar",
    test: 123
};

You can then access properties this way:

alert(obj.foo);

Note that this notation only works inside of object litterals. If you want to set a property from outside, also use the dot notation:

obj.foo = "hi";