Untitled

<html>
	<head>
		<title>lab</title>
	</head>
	<body>
		<table border="1"></table>
		<input id="lastname" type="text"/><button id="find">Click to find</button>
		<div id="output"></div>

		<script>
		contactManager = {
			protoContact : {
				toString : function() {
					return this.first + " " + this.last + " " + this.email;
				}
			},

			Contact : function() {},

			contacts : [],

			build : function(params) {
				this.Contact.prototype = this.protoContact;
				var newContact = new this.Contact();
				for (var k in params)
					newContact[k] = params[k];
				newContact.id = Math.random();
				this.contacts.push(newContact);
			},

			find : function(val, field) {
				if (field === undefined)
					field = "last";
				for (var i=0; i<this.contacts.length; i++)
					if (this.contacts[i][field] == val)
						return this.contacts[i];
			}

		};

		test = function() {
			contactManager.build({ first:"Joe1", last:"Smith1", email: "joesmith1@gmail.com"});
			contactManager.build({ first:"Joe2", last:"Smith2", email: "joesmith2@gmail.com"});
			contactManager.build({ first:"Joe3", last:"Smith3", email: "joesmith3@gmail.com"});
			c1 = contactManager.find("Smith2");
			console.log(c1);
			document.getElementById("output").innerHTML = "Found " + c1.email;
			c2 = contactManager.find("Joe3", "first");
			console.log(c2);
			document.getElementById("output").innerHTML += "<br/>Found " + c2.email;
		}

		test();

		document.getElementById("find").addEventListener("click", function() {
			var found = contactManager.find(document.getElementById("lastname").value);
			document.getElementById("output").innerHTML +=
				"<br/>" + found.toString();
			var row = document.getElementsByClassName(found.id)[0];
			row.style.background="yellow";
			setTimeout(function(){row.style.background="";},1000);
		});

		h1 = document.createElement("h1");
		h1.innerHTML="Contacts";
		document.body.insertBefore(h1, document.querySelector("input"));

		render = function(contacts) {
			createCell = function(text, parent) {
				var tdCell = document.createElement("td");
				tdCell.innerHTML = text;
				if (parent)
					parent.appendChild(tdCell);
				return tdCell;
			}

			table = document.querySelector("table");
			table.innerHTML="";
			for (var i=0; i<contacts.length; i++) {
				var tr = document.createElement("tr");
				for (var k in contacts[i])
					if (contacts[i].hasOwnProperty(k))
						createCell(contacts[i][k], tr);
				table.appendChild(tr);
				tr.setAttribute("class", contacts[i].id);
				createCell("<button>Delete</button>",tr);
			}
		}

		render(contactManager.contacts);

		table.addEventListener("click", function(e) {
			var t = e.target;
			if (e.target.tagName.toLowerCase()!="button")
				return;
			var id = t.parentNode.parentNode.getAttribute("class");
			var contact = contactManager.find(id, "id");
			contactManager.contacts.splice(contactManager.contacts.indexOf(contact),1);
			render(contactManager.contacts);
		});
		</script>
	</body>
</html>
---


>>> car.name

"Corvette"

>>> car.print()

Car? is Corvette

index.html (line 16)

undefined

>>> truck = { name : "hummer" }

Object { name=

"hummer"

}

>>> truck.print = car.print

function()

>>> truck.print()

Car? is hummer

index.html (line 16)

undefined

>>> window.myPrint = car.print

function()

>>> myPrint()

Car? is

index.html (line 16)

undefined

>>> x= undefined

undefined

>>> if (x === undefined) alert("yes")

undefined

>>> if (x === null) alert("yes")

undefined


----


>>> accessors.get()

"hello"

>>> accessors.set("different message")

undefined

>>> accessors.get()

"different message"


>>> a = { id : 4 }

Object { id=

4

}

>>> b = Object.create(a)

Object { id=

4

}

>>> b.name = "X"

"X"

>>> b.name

"X"

>>> b.id

4

>>> b.id = 7

7

>>> b

Object { name=

"X"

, id=

7

}

>>> a

Object { id=

4

}

>>> delete b.id

true

>>> b

Object { name=

"X"

, id=

4

}

>>> Object.getPrototypeOf(b)

Object { id=

4

}

>>> Object.getPrototypeOf(b) === a

true

>>> b.name

"X"

>>> b.hasOwnProperty("name")

true

>>> b.hasOwnProperty("id")

false

>>> b.id

4

>>> for (var k in b) { console.log(k) }

name

id

>>> c = Object.create(b)

Object { name=

"X"

, id=

4

}

>>> d = Object.create(c)

Object { name=

"X"

, id=

4

}

>>> c.foo = "monkey"

"monkey"

>>> d.foo

"monkey"