This is JavaScript Array extended. It can throw events change
, insert
, update
, remove
. You can use it for something like light version of Backbone Collection.
Initialize new array with items: item1, item2, ..., itemN
.
List of Attached Events.
var fruits = new Arr('apple', 'orange', 'pineapple');
fruits.on('change', function(event) {
console.log('fruits list is changed.');
});
// fruits.events
// [{
// "name": "change",
// "handler": function() { ... }
// }]
fruits.push('mango');
// fruits list is changed.
// fruits
// ['apple', 'orange', 'pineapple', 'mango']
Standard property [length
](Standart accessor methods supported).
Example:
var fruits = new Arr('apple', 'orange', 'pineapple');
fruits.get(0);
// apple
fruits.get(10, 'lime'); // trying to get undefined element - return defaultValue
// lime
fruits.get(20); // trying to get undefined element
// undefined
concat()
Returns a new array comprised of this array joined with other array(s) and/or value(s).join()
Joins all elements of an array into a string.slice()
Extracts a section of an array and returns a new array.toString()
Returns a string representing the array and its elements. Overrides theObject.prototype.toString()
method.toLocaleString()
Returns a localized string representing the array and its elements. Overrides theObject.prototype.toLocaleString()
method.indexOf()
Returns the first (least) index of an element within the array equal to the specified value, or -1 if none is found.lastIndexOf()
Returns the last (greatest) index of an element within the array equal to the specified value, or -1 if none is found.
and other methods.
Notice: Traditional mutator arr[index] = value
do not trigger events change
, update
. Use method set(index, value)
instead arr[index] = value
.
Set value by index. Will be triggered event change
, update
.
Example:
var fruits = new Arr('apple', 'orange', 'pineapple');
fruits.set(0, 'banana');
// ['banana', 'orange', 'pineapple']
fruits.set(1, 'lime');
// ['banana', 'lime', 'pineapple']
fruits.set(3, 'nut');
// ['banana', 'lime', 'pineapple', 'nut']
Insert array of items. Will be triggered events change
, insert
.
Example:
var fruits = new Arr();
fruits.insert('apple', 'orange', 'pineapple');
// ['apple', 'orange', 'pineapple']
Update item if handler
return true
. Will be triggered event change
if one or more items updated.
handler
can recive data:
value
(mixed) current valueindex
(number) current index
Example:
var fruits = new Arr('apple', 'orange', 'pineapple');
fruits.update(function(value, index) {
if (index === 2) {
return 'lime'; // "return" not undefined value for update item
}
});
// ['apple', 'orange', 'lime']
fruits.update(function(value, index) {
return index;
});
// [0, 1, 2]
Remove item if handler
return true
. Will be triggered event change
if one or more items removed.
Example:
var fruits = new Arr('apple', 'orange', 'pineapple');
fruits.remove(function(value, index) {
if (value.indexOf('apple') !== -1) {
return true;
}
});
// ['orange']
Method remove()
without arguments - will remove all items.
Example:
var fruits = new Arr('apple', 'orange', 'pineapple');
fruits.remove();
// fruits
// []
Each mutator method throw event change
. How? You can read in section Events.
pop()
Removes the last element from an array and returns that element.push()
Adds one or more elements to the end of an array and returns the new length of the array.reverse()
Reverses the order of the elements of an array — the first becomes the last, and the last becomes the first.shift()
Removes the first element from an array and returns that element.sort()
Sorts the elements of an array in place and returns the array.splice()
Adds and/or removes elements from an array.unshift()
Adds one or more elements to the front of an array and returns the new length of the array.
and other methods.
Sometimes you need to push array of items to Arr
. You can push array of items in this way (note: now you can use method insert()
):
var fruits = new Arr;
fruits.push.apply(fruits, ['apple', 'orange', 'pineapple']);
// fruits
// ['apple', 'orange', 'pineapple']
For remove item(s) from Arr
you can use traditional method splice()
(note: now you can use method remove()
).
var fruits = new Arr('apple', 'orange', 'pineapple');
fruits.splice(0, 1); // remove first item
// fruits
// ['orange', 'pineapple']
forEach()
Calls a function for each element in the array.every()
Returns true if every element in this array satisfies the provided testing function.some()
Returns true if at least one element in this array satisfies the provided testing function.filter()
Creates a new array with all of the elements of this array for which the provided filtering function returns true.map()
Creates a new array with the results of calling a provided function on every element in this array.reduce()
Apply a function against an accumulator and each value of the array (from left-to-right) as to reduce it to a single value.reduceRight()
Apply a function against an accumulator and each value of the array (from right-to-left) as to reduce it to a single value.
and other methods.
You can use method filter()
for searching items by conditions.
Example:
var fruits = new Arr('apple', 'orange', 'pineapple');
var fruitsWithWordApple = fruits.filter(function(value, index) {
if (value.indexOf('apple') !== -1) {
return true;
} else {
return false;
}
});
// fruitsWithWordApple
// ['apple', 'pineapple']
Instance of Arr can throw events change
, insert
, update
, remove
.
How to use events? You can use array events like events in Backbone Collection.
var fruits = new Arr('apple', 'orange', 'pineapple');
fruits.on('change', function(event) {
// event
// {
// "type": "insert",
// "items": ['mongo']
// }
console.log('fruits list is changed.');
});
// fruits.events
// [{
// "name": "change",
// "handler": function() { ... }
// }]
fruits.push('mango');
// fruits list is changed.
// fruits
// ['apple', 'orange', 'pineapple', 'mango']
Notice: Traditional mutator arr[index] = value
do not trigger event change
. Use method set(index, value)
instead arr[index] = value
.
Attach event handler.
handler
can recive event
that have data:
type
(string) can beinsert
,update
,remove
items
(array) are items that was inserted, updated or removed
Example:
var fruits = new Arr('apple', 'orange', 'pineapple');
fruits.on('change', function(event) {
// event
// {
// "type": "insert",
// "items": ['mango']
// }
console.log('fruits list is changed.');
});
fruits.push('mango');
Remove attached event handler.
Example:
var fruits = new Arr('apple', 'orange', 'pineapple');
var changeHandler = function(event) {
console.log('fruits list is changed.');
};
fruits.on('change', changeHandler);
fruits.off('change', changeHandler); // remove only one handler
fruits.off('change'); // remove all handlers attached to event change
Trigger some event.
var fruits = new Arr('apple', 'orange', 'pineapple');
fruits.on('change', function(event) {
console.log('fruits list is changed.');
});
fruits.trigger('change');
// fruits list is changed.
Send server updates when Arr
is changed.
var products = new Arr(
{
id: 1,
name: 'apple'
},
{
id: 2,
name: 'orange'
},
{
id: 3,
name: 'pineapple'
}
);
products.on('change', function(event) {
// products are changed
// you can use event.type == 'insert' or 'update' or 'remove' to detect items that you need to update on the server
// $ is link on jQuery
$.post('/products', products)
.fail(function() {
alert('error');
})
.done(function(updatedProducts) {
alert('products are updated');
});
});
products.push({
name: 'lime'
});