admin管理员组

文章数量:1026989

Why is the item variable undefined in this Backbone example?

var Action = Backbone.Model.extend({
defaults: {
    "selected": false,
    "name": "First Action",
    "targetDate": "10-04-2014"
}
});

var Actions = Backbone.Collection.extend({
    model: Action
});

var actionCollection = new Actions( [new Action(), new Action(), new Action(), new Action()]);

_.each(actionCollection, function(item) {
    alert(item);
});

jsFiddle here: /

Why is the item variable undefined in this Backbone example?

var Action = Backbone.Model.extend({
defaults: {
    "selected": false,
    "name": "First Action",
    "targetDate": "10-04-2014"
}
});

var Actions = Backbone.Collection.extend({
    model: Action
});

var actionCollection = new Actions( [new Action(), new Action(), new Action(), new Action()]);

_.each(actionCollection, function(item) {
    alert(item);
});

jsFiddle here: http://jsfiddle/netroworx/KLYL9/

  • javascript
  • jquery
  • backbone.js
Share Improve this question asked Jul 1, 2013 at 9:29 Greg Pagendam-TurnerGreg Pagendam-Turner 2,5525 gold badges35 silver badges52 bronze badges
Add a ment  | 

2 Answers 2

Reset to default 10

Change it to:

actionCollection.each(function(item) {
        alert(item);
});

And it works fine.

This because actionCollection is not an array, so _.each(collection) does not work but collection.each does because that function is build into Backbone collection.

That being said, this also works:

_.each(actionCollection.toJSON(), function(item) {
        alert(item);
});

Because now the collection is an actual array.

_.each accepts an array as first argument, but you passed a Collection.

Just use the Collection.each method:

actionCollection.each(function(item){
  //do stuff with item
});

Why is the item variable undefined in this Backbone example?

var Action = Backbone.Model.extend({
defaults: {
    "selected": false,
    "name": "First Action",
    "targetDate": "10-04-2014"
}
});

var Actions = Backbone.Collection.extend({
    model: Action
});

var actionCollection = new Actions( [new Action(), new Action(), new Action(), new Action()]);

_.each(actionCollection, function(item) {
    alert(item);
});

jsFiddle here: /

Why is the item variable undefined in this Backbone example?

var Action = Backbone.Model.extend({
defaults: {
    "selected": false,
    "name": "First Action",
    "targetDate": "10-04-2014"
}
});

var Actions = Backbone.Collection.extend({
    model: Action
});

var actionCollection = new Actions( [new Action(), new Action(), new Action(), new Action()]);

_.each(actionCollection, function(item) {
    alert(item);
});

jsFiddle here: http://jsfiddle/netroworx/KLYL9/

  • javascript
  • jquery
  • backbone.js
Share Improve this question asked Jul 1, 2013 at 9:29 Greg Pagendam-TurnerGreg Pagendam-Turner 2,5525 gold badges35 silver badges52 bronze badges
Add a ment  | 

2 Answers 2

Reset to default 10

Change it to:

actionCollection.each(function(item) {
        alert(item);
});

And it works fine.

This because actionCollection is not an array, so _.each(collection) does not work but collection.each does because that function is build into Backbone collection.

That being said, this also works:

_.each(actionCollection.toJSON(), function(item) {
        alert(item);
});

Because now the collection is an actual array.

_.each accepts an array as first argument, but you passed a Collection.

Just use the Collection.each method:

actionCollection.each(function(item){
  //do stuff with item
});

本文标签： javascriptBackbone each undefinedStack Overflow

版权声明：本文标题：javascript - Backbone each undefined - Stack Overflow 内容由热心网友自发贡献，该文观点仅代表作者本人， 转载请联系作者并注明出处：http://it.en369.cn/questions/1745655966a2161598.html， 本站仅提供信息存储空间服务，不拥有所有权，不承担相关法律责任。如发现本站有涉嫌抄袭侵权/违法违规的内容，一经查实，本站将立刻删除。