Storing knockout view model data in a database and fetching it back

I am currently working on a web form that utilizes knockout, and I need to add a new feature that allows users to save the form as a draft in the database. Later on, they should be able to load it again to make modifications or submit it.

Is there a built-in function within the knockout framework that I can use to serialize the viewmodel into another format such as JSON? This way, I could easily save it to the database and then load it back to populate my view without having to manually fill each property one by one.

While I am aware that I can save the viewmodel as a JSON object in the database and then retrieve it to update each property individually, I am looking for a more efficient solution. It would be great if there was a feature that allows me to serialize and deserialize the entire viewmodel at once, making the process much simpler. Given that my viewmodel has many properties, I prefer not to write code lines for each property like the example below:


var someJSON = /* fetched the saved viewmodel as a json */;
var parsed = JSON.parse(someJSON);

// Update view model properties
viewModel.firstName(parsed.firstName);
viewModel.pets(parsed.pets);

Answer №1

To easily update your view model properties, consider using the mapping plugin instead of manually writing code:

var someData = /* retrieve the saved viewmodel data as JSON */;
var parsedJSON = JSON.parse(someData);

// Use the mapping plugin to update view model properties
viewModel = ko.mapping.fromJS(parsedJSON);

Answer №2

While the mapping plugin mentioned in previous answers can be used, it has its flaws that may not make it ideal for all situations.

One major issue is that object properties are not automatically converted into observables.

var data = {
    name: 'John',
    age: 30
};

var viewModel = ko.mapping.fromJS(data);

if(!ko.isObservable(viewModel.age)) console.log('Conversion failed!');

Exploring the option of forking the plugin was considered, but ultimately deemed unnecessary. Instead, a post-processing step was implemented to identify non-observable properties containing objects and convert them as needed.

Similar questions

If you have not found the answer to your question or you are interested in this topic, then look at other similar questions below or use the search

Tips for debugging Angular applications with Firebug

I've encountered an issue while developing an AngularJS app that fetches data from the Firebase cloud. The data is successfully displayed on the page, however, during debugging of my controller, I noticed that the variable appears to be empty. Why is ...

Is it possible to utilize Ajax submit requests within a (function($){...}(jQuery)); block?

As a PHP developer with some knowledge of JavaScript, I am currently using AJAX to send requests to the server. I recently came across the practice of enclosing all code within an anonymous JavaScript function like: (function($){ //code here }(jQuery)). Fo ...

Is it possible to iterate through div elements using .each while incorporating .append within an AJAX call?

After sending AJAX requests and receiving HTML with multiple div elements (.card), I am using .append to add new .card elements after each request, creating an infinite scroll effect. However, I am facing issues when trying to use .each to iterate over all ...

Errors always occur when making POST requests in SAPUI5, leading to a 500 Server Error specifically related to OData

Currently diving into the world of SAPUI5 and OData, I am in the process of creating a basic application that showcases employee data in a table. The objective is to add a new employee to the table whose information will be stored in the SAP backend. Whil ...

Trouble encountered while attempting to parse JSON with GSON library

Currently, I am in the process of parsing a local JSON file using the GSON Library. Below is the structure of my JSON: { "employees":[ { "id":100, "name":"Ranjith" }, { "id":101, "name":"Satheesh" }] } My task is to showcase this da ...

Automatically reset the form after submission in CakePHP 1.3

I've encountered an issue with my report form that is linked multiple times on a page to a jQuery dialog box. To prevent cross-posting, I added a random string to the submission process. After successfully submitting the form on a single page access, ...

What is the best way to send variables from JavaScript to PHP while utilizing Ajax technology?

While I have noticed similar questions like this one before, I want to address my specific concerns. In previous examples, the questioner referred to using Ajax in a format similar to this: $.ajax({ type: "POST", url: 'logtime.php', ...

Ensuring Data Consistency: Using TypeScript to Strongly Type Arrays with Mixed Variable Types

I have a JSON array that may contain objects of two types, defined by IPerson and ICompany. [ { "Name" : "Bob", "Age" : 50, "Address": "New Jersey"}, { "Name" : "AB ...

Creating a cube with unique textures on each face in three.js r81: What's the best way to achieve this?

After updating to the latest version of three.js, I encountered an issue where THREE.ImageUtils.loadTexture no longer works. As a result, I tried searching for examples of cubes with different faces, but they all utilized the outdated technique "new THREE. ...

An issue has arisen with AngularJS and Twitter Bootstrap, displaying an error message stating that the function element.focus

I recently implemented the angularjs twitter bootstrap datepicker and everything seemed to be working smoothly. However, I encountered an error when trying to click on the text box for the popup datepicker. This issue has left me puzzled as I am still new ...

asp.net website fully compressed using GZip

I am currently developing a Single Page Application (SPA) and I have encountered an issue with the size of my JavaScript files, which are about 300 KB. Additionally, the web services (.asmx files) that generate jsdebug files add another 350 KB to the bundl ...

Utilizing JavaScript to call functions from an ASP.NET code file

I am in need of assistance with integrating a JavaScript-based timeline that requires data from an SQL server. I have already developed the queries and JSON conversions using C#.NET functions within a code file associated with an .aspx page. As a newcomer ...

The use of Next.js v12 middleware is incompatible with both node-fetch and axios

I am facing an issue while developing a middleware that fetches user data from an external endpoint using Axios. Surprisingly, Axios is not functioning properly within the middleware. Below is the error message I encountered when using node-fetch: Module b ...

Angular2's hidden feature isn't functioning properly

There is a common suggestion to use *ngIf better than [hidden] but in my scenario, I want to keep the element in the DOM without it being visible. In my component.html file, I have: <article #articleId id="bodyArticle" [hidden]="isClicked"></art ...

What is the most effective method to patiently anticipate a specific duration for a function's output?

I am faced with a situation where I have two functions at hand. One function performs complex logic, while the other wraps this function to provide either the result of computation or an error message after a specified amount of time t. Consider the follo ...

looping through an ajax function with addEventListener

Apologies in advance for any errors in my English. My task involves creating a simple webpage with just 2 links. When one of these links is clicked, it should load the content of a specific .html file on the same page. For example: clicking on link 1 (wi ...

Which is better for scrolling in Angular 2+: using HostListener or window.pageYOffset?

Which syntax is best for maximizing performance in Angular 2+? Is it necessary to use HostListener, or is it simpler to obtain the scroll position using the onscroll window event and pageYOffset? @HostListener('window:scroll', ['$event&ap ...

How can I transfer a JavaScript value to PHP for storage in an SQL database?

<script> var latitudeVal = document.getElementById("latitude"); var longitudeVal = document.getElementById("longitude"); function getLocation() { if (navigator.geolocation) { navigator.geolocation.getCurrentPosition(showPosition); ...

Efficiently handling multiple responses in Express.js per single request

Currently exploring Node.js and working on a bot utilizing Dialogflow. I am aiming to establish a straightforward process: Step 1: Dialogflow sends a POST request with parameter param1 Step 2: My application replies with a waiting message (e.g., "your re ...

Troubleshooting: Issue with passing parameters in Wordpress ajax function

In my Wordpress Ajax implementation, I am facing an issue where the parameter value metakey: id is not being passed to $_POST["metakey"]. As a result, when I do a var_dump($_POST), it shows array(0) { }. If I manually set a static value for the variable i ...