Collections are ordered sets of Models. We just need to extend the backbone's collection class to create our own collection. Any event that is triggered on a model in a collection will also be triggered on the collection directly. This allows you to listen for changes to specific attributes in any model in a collection.
The following table lists down all the methods which you can use to manipulate the BackboneJS-Collection −
| S.No. |
Methods & Description |
| 1 |
extend
Extends the backbone's collection class to create a collection.
|
| 2 |
model
To specify the model class, we need to override the model property of the collection class.
|
| 3 |
initialize
When a model instance is created, it is invoked by defining the initialize function when the collection is created.
|
| 4 |
models
Array of models which are created inside the collection.
|
| 5 |
toJSON
Returns the copy of the attributes of a model using the JSON format in the collection.
|
| 6 |
sync
It represents the state of the model and uses the Backbone.sync to display the state of the collection.
|
| 7 |
add
Add a model or array of models to the collection.
|
| 8 |
remove
Removes a model or array of models from the collection.
|
| 9 |
reset
It resets the collection and populates with new array of models or will empty the entire collection.
|
| 10 |
set
It is used to update the collection with a set of items in a model. If any new model is found, the items will be added to that model.
|
| 11 |
get
It is used to retrieve the model from a collection by using the idor cid.
|
| 12 |
at
Retrieve the model from a collection by using specified index.
|
| 13 |
push
It is similar to the add() method which takes the array of models and pushes the models to the collection.
|
| 14 |
pop
It is similar to the remove() method which takes the array of models and removes the models from the collection.
|
| 15 |
unshift
Add a specified model at the beginning of a collection.
|
| 16 |
shift
It removes the first item from the collection.
|
| 17 |
slice
Displays the shallow copy of the elements from the collection model.
|
| 18 |
length
Counts the number of models in the collection.
|
| 19 |
comparator
It is used to sort the items in the collection.
|
| 20 |
sort
Sorts the items in the collection and uses comparator property in order to sort the items.
|
| 21 |
pluck
Retrieves the attributes from the model in the collection.
|
| 22 |
where
It is used to display the model by using the matched attribute in the collection.
|
| 23 |
findWhere
It returns the model, that matches the specified attribute in the collection.
|
| 24 |
url
It creates an instance of the collection and returns where resources are located.
|
| 25 |
parse
Returns the collection's data by passing through the response object and represents the data in JSON format.
|
| 26 |
clone
It returns the shallow copy of the specified object.
|
| 27 |
fetch
It extracts the data from the model in the collection using the sync method.
|
| 28 |
create
It creates a new instance of the model in the collection.
|
| S.No. |
Methods & Description |
| 1 |
_.each(list, iteratee, [context])
Iterates each of the elements in the collection using the iteratee function.
|
| 2 |
_.map(list, iteratee, [context])
It maps each value and displays them in a new array of values using the iteratee function.
|
| 3 |
_.reduce(list, iteratee, memo, [context])
It reduces the list of values into a single value and it also known as inject and foldl.
|
| 4 |
_.reduceRight(list, iteratee, memo, [context])
It is the right associative version of reduce.
|
| 5 |
_.find(list, predicate, [context])
It finds each value and returns the first one which passes the predicate or test.
|
| 6 |
_.filter(list, predicate, [context])
It filters each value and returns the array of values which passes the predicate or test.
|
| 7 |
_.reject(list, predicate, [context])
It returns the rejected elements in the list which do not pass the predicted values.
|
| 8 |
_.every(list, predicate, [context])
It returns true, if elements in the list pass the predicted values.
|
| 9 |
_.some(list, predicate, [context])
It returns true, if elements in the list pass the predicted values.
|
| 10 |
_.contains(list, value, [fromIndex])
It returns true, if a value is present in the list.
|
| 11 |
_.invoke(list, methodName, *arguments)
It invokes the method name using methodName() on each value in the list.
|
| 12 |
_.max(list, [iteratee], [context])
It specifies the maximum value in the list.
|
| 13 |
_.min(list, [iteratee], [context])
It specifies the minimum value in the list.
|
| 14 |
_.sortBy(list, [iteratee], [context])
It returns the sorted elements in the ascending order by using iteratee in the list.
|
| 15 |
_.groupBy(list, [iteratee], [context])
It divides the collection values into the sets, grouped by using the iteratee in the list.
|
| 16 |
_.shuffle(list)
It returns the shuffled copy of the list.
|
| 17 |
_.toArray(list)
It defines an array of the list.
|
| 18 |
_.size(list)
It defines the number of values in the list.
|
| 19 |
_.first(array, [n])
It specifies the first element of the array in the list.
|
| 20 |
_.initial(array, [n])
It returns everything, but specifies the last entry of the array in the list.
|
| 21 |
_.last(array, [n])
It specifies the last element of the array in the list.
|
| 22 |
_.rest(array, [index])
It defines the remaining elements in the array.
|
| 23 |
_.without(array, *values)
It returns the values of all instances which are removed in the list.
|
| 24 |
_.indexOf(array, value, [isSorted])
It returns the value if it is found at a specified index or returns -1, if it is not found.
|
| 25 |
_.indexOf(array, value, [fromIndex])
It returns the last occurrence of the value in the array or returns -1, if it is not found.
|
| 26 |
_.isEmpty(object)
It returns true if there are no values in the list.
|
| 27 |
_.chain(obj)
It returns a wrapped object.
|
