How to Bind Array Of Objects From Promise Knockout.js?

In order to bind an array of objects from a promise in knockout.js, you can first define an observable array in your viewmodel. Then, you can use the then() method on the promise object to populate the observable array with the data once the promise is resolved. You can also use the ko.applyBindings() method to bind the data to the HTML elements in your view.

How to access properties of objects in knockout.js?

You can access properties of objects in knockout.js using the dot notation or square bracket notation. Here are some examples:

1. Using dot notation:

1
2
3
4
5
6
7

var myViewModel = {
  firstName: 'John',
  lastName: 'Doe'
};

console.log(myViewModel.firstName); // Output: John
console.log(myViewModel.lastName); // Output: Doe

1. Using square bracket notation:

1
2
3
4
5
6
7

var myViewModel = {
  firstName: 'John',
  lastName: 'Doe'
};

console.log(myViewModel['firstName']); // Output: John
console.log(myViewModel['lastName']); // Output: Doe

You can also access nested properties of objects using the dot or square bracket notation:

1
2
3
4
5
6
7
8
9

var myViewModel = {
  person: {
    firstName: 'John',
    lastName: 'Doe'
  }
};

console.log(myViewModel.person.firstName); // Output: John
console.log(myViewModel['person']['lastName']); // Output: Doe

In knockout.js, you can access object properties within the HTML template using data binding syntax, for example:

1

<div data-bind="text: person.firstName"></div>

This would display the value of the first name property of the person object in the HTML.

What is the if binding in knockout.js?

The if binding in knockout.js is used to conditionally show or hide a DOM element based on a specified expression. It works by evaluating the expression provided and rendering the element only if the expression evaluates to true. If the expression evaluates to false, the element will not be displayed in the DOM. This allows for dynamic manipulation of the DOM based on changing data and conditions in the view model.

What is the checked binding in knockout.js?

The checked binding in Knockout.js is used to bind a checkbox or radio button element to a property in the view model. It sets or gets the value of the property based on the checked state of the checkbox or radio button. This binding is commonly used to enable two-way data binding for these input elements.

How to add new object to array in knockout.js?

To add a new object to an array in knockout.js, you can use the following steps:

1. Define an observable array in your view model:

1
2
3

var viewModel = {
    items: ko.observableArray([])
};

1. Add a function to your view model that will add a new object to the observable array:

1
2
3
4

viewModel.addItem = function() {
    var newItem = { name: 'New Item' };
    viewModel.items.push(newItem);
};

1. Call the addItem function to add a new object to the array:

1

viewModel.addItem();

This will add a new object with the property name set to 'New Item' to the items array in your view model.

What is the component binding in knockout.js?

Component binding in knockout.js is a feature that allows you to create reusable, encapsulated components that can be easily added to your web application. By using component binding, you can break down your application into smaller, more manageable pieces, making it easier to maintain and update.

With component binding, you can define a component template, view model, and any necessary data bindings in a separate file, and then use a custom binding in your HTML code to add the component to your application. This allows you to reuse the same component in multiple places within your application, saving you time and effort.

Overall, component binding in knockout.js helps to promote code reusability, maintainability, and organization in your web applications.