nola’s gists

nola / objects-as-parameter.js

Last active December 30, 2015 20:39

Passing objects to functions.If you pass an object (i.e. a non-primitive value, such as Array or a user-defined object) as a parameter, and the function changes the object's properties, that change is visible outside the function, as shown in the following example:

	var myFunc;
	var num = 0;
	if (num === 0){
	myFunc = function(theObject) {
	theObject.make = "Toyota";
	theObject.year = "2003";
	return theObject;
	};
	}

nola / no-name-function.js

Created December 9, 2013 22:28

stores the function in the variable "square" so you call square()

	var square = function(number) {return number * number};
	var x = square(4) //x gets the value 16

nola / monitor.js

Last active December 30, 2015 20:29

Monitor events on the DOM

	//put this in the console
	monitorEvents(window)

	//only mouse events
	monitorEvents(window, 'mouse')

	//only keyboard events
	monitorEvents(window, 'key')

	//only scroll activity

nola / on-event.js

Last active December 30, 2015 19:49

jquery .on with event. New and Old way with bind

	$('body').on({
	click: function() {
	event.preventDefault();
	console.log('item anchor clicked');
	},
	mouseenter: function() {
	console.log('enter!');
	}
	});

nola / in.js

Created December 1, 2013 04:21

propNameOrNumber in objectName

	// Arrays
	var trees = new Array("redwood", "bay", "cedar", "oak", "maple");
	0 in trees; // returns true
	3 in trees; // returns true
	6 in trees; // returns false
	"bay" in trees; // returns false (you must specify the index number,
	// not the value at that index)
	"length" in trees; // returns true (length is an Array property)

	// Predefined objects

nola / delete.js

Last active December 29, 2015 20:19

-//The delete operator deletes an object, an object's property, or an element at a specified index in an array. Syntax:
-delete objectName;
-delete objectName.property;
-delete objectName[index];
-delete property; // legal only within a with statement
-//If the delete operator succeeds, it sets the property or element to undefined.
-//The delete operator returns true if the operation is possible; it returns false if the operation is not possible.
-x = 42;

nola / shortif.js

Created November 30, 2013 18:40

short hand if statement.

	var age = 19;
	if(age >= 18){
	var status = "adult";
	}else{
	var status = "minor";
	}


	//short hand version
	var status = (age >= 18) ? "adult" : "minor";

nola / two-objs.js

Last active December 29, 2015 14:49

The following example creates myHonda with three properties. Note that the engine property is also an object with its own properties.

	var myHonda = {color: "red", wheels: 4, engine: {cylinders: 4, size: 2.2}};

	//console edits and results
	myHonda.color
	"red"
	myHonda.engine
	Object {cylinders: 4, size: 2.2}
	myHonda.engine.size
	2.2
	myHonda.engine.size = "3.3"

nola / if-true-createObject.js

Created November 28, 2013 03:54

The following statement creates an object and assigns it to the variable x if and only if the expression cond is true:

if (cond) var x = {hi: "there"};

nola / for-in.js

Last active December 29, 2015 14:49

Enumerating over all the properties in an object. Find out whats in there.

	//create the object with properties & values.
	var myCar = new Object();
	myCar.make = "Ford";
	myCar.model = "Mustang";
	myCar.year = 1969;

	//then LOOP(enumerate) through all the properties of the object myCar
	function showProps(obj, objName) {
	var result = "";
	for (var i in obj) {

Cyril Celestine nola