Using default JavaScriptSerializer to bind DateTime to knockout view model

Recently, I started using knockout and encountered a problem with DateTime Serialization and Deserialization when using the JavaScriptSerializer.

I modified the gifts model in Steve's koListEditor example from his blog to include a new field for Modified DateTime:

public class GiftModel
{
    public string Title { get; set; }
    public double Price { get; set; }
    public DateTime Modified { get; set; }
}

After updating the Index.aspx to include the new field:

<asp:Content ContentPlaceHolderID="MainContent" runat="server">
    <h1>Gift list editor</h1>

    <p>You have requested <span data-bind="text: gifts().length">&nbsp;</span> gift(s)</p>

    <form class="giftListEditor">
        <table> 
            <tbody data-bind="template: { name: 'giftRowTemplate', foreach: gifts }"></tbody> 
        </table>

        <button data-bind="click: addGift">Add Gift</button>
        <button data-bind="enable: gifts().length > 0" type="submit">Submit</button>
    </form>

    <script type="text/html" id="giftRowTemplate"> 
        <tr> 
            <td>Gift name: <input class="required" data-bind="value: Title, uniqueName: true"/></td> 
            <td>Price: \$ <input class="required number" data-bind="value: Price, uniqueName: true"/></td> 
            <td>Modified:  <input class="required date" data-bind="value: Modified, uniqueName: true"/></td> 
            <td><a href="#" data-bind="click: function() { viewModel.removeGift($data) }">Delete</a></td> 
        </tr>
    </script>

    <script type="text/javascript">
        var initialData = <%= new JavaScriptSerializer().Serialize(Model) %>;
        var viewModel = { 
            gifts : ko.observableArray(initialData), 

            addGift: function () { 
                this.gifts.push({ Title: "", Price: "", Modified:"" }); 
            },

            removeGift: function (gift) { 
                this.gifts.remove(gift); 
            },

            save: function() { 
                ko.utils.postJson(location.href, { gifts: this.gifts }); 
            } 
        }; 

        ko.applyBindings(document.body, viewModel);
        $("form").validate({ submitHandler: function() { viewModel.save() } });
    </script> </asp:Content>

However, while serializing the Model with JavaScriptSerializer:

var initialData = <%= new JavaScriptSerializer().Serialize(Model) %>;

The Modified Date is not being formatted correctly.

Another issue arises when using UK dates like 25/01/2011, which causes an exception in JavaScriptSerializer.Deserialize:

25/01/2011 is not a valid value for DateTime.

Despite facing these problems, my main concern is if anyone has successfully used knockout with MVC 2 and managed to get the JavaScriptSerializer working properly with DateTimes. I am open to suggestions or existing solutions to tackle this issue.

You can find the updated version of Steve Sanderson's koListEditor code here:

Code on my skydrive

Thank you,

Dave

Answer №1

If you're faced with this scenario, you essentially have two choices to consider. One option is to go for a straightforward solution by utilizing a dedicated view model object that contains preformatted date-time values in string format. This is the method I usually prefer as it allows me to easily tryparse the date value for validation purposes.

Alternatively, you could explore the possibility of implementing a custom data binding. More information on how to do this can be found here. Opting for this approach tends to be more elegant. The beauty of this method is that you can integrate your UI generation code into the binding process, thereby enabling you to seamlessly incorporate a date picker into your user interface.

Answer №2

Although not the most elegant method, this code snippet does get the job done:


data-bind="value: eval('new ' + Modified.slice(1,-1)), uniqueName: true"

It's important to note that using <code>eval
could potentially pose security risks depending on the specific context in which it is used.

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

Retrieving a list of numbers separated by commas from an array

Currently, I'm retrieving data from a MYSQL database by executing the following SQL command: SELECT GROUP_CONCAT(MemberMemberId SEPARATOR ',') AS MemberMemberId FROM member_events WHERE event_date = "2000-01-01" AND Eve ...

React does not allow for images to be used as background elements

I am currently working on a web page and I have attempted to use both jpg and png images as backgrounds, but they do not seem to display on the page. import './Entrada.css' const Entrada = () => { return( <div style={{ b ...

A guide on combining two similar entities in Laravel

I require assistance with merging two similar objects into one object in Laravel. How can this be achieved? Below are the objects: {"course_code":"UGRC110","venue_id":22,"exam_date":"May 6, 2017","exam_time":"3:30 pm","student_no":400} and {"course_co ...

Issue: Unable to locate module - Unable to resolve 'core-js/modules/es.error.cause.js'

I've incorporated Vuexy Dashboard into my project, which utilizes Vue 2. Now, I'm in the process of upgrading it to Vue 3. However, I have encountered an error that has me stuck. Any assistance with this issue would be greatly appreciated. Thank ...

Is the xmlhttprequest timeout/abort feature not functioning as anticipated?

Check out this snippet of my AJAX function: /** * This function initiates an AJAX request * * @param url The URL to call (located in the /ajax/ directory) * @param data The data to send (will be serialized with JSON) * @param callback The fu ...

Partially extended texture in Three.js

Currently, I am using the Collada loader in Three.js r65 to load my 3D object. Upon loading, I apply a texture to all parts of the model using the following code snippet. var loader = new THREE.ColladaLoader(); loader.options.convertUpAxis = true; loader ...

Altering the hover functionality for dynamically created class elements

I have a vision to create a unique e-commerce storefront with tile design, featuring an item thumbnail that reveals the item name upon hovering. I found inspiration from this example, but I want the item name to slide up smoothly on hover, rather than simp ...

What is the best way to incorporate a third-party element into Vue using a script tag?

I am in the process of developing a website and I would like to include a widget that links to a podcast on BuzzSprout. Initially, I created the site using HTML to test out different designs, but now I am looking to transition it to VueJS. In my HTML vers ...

Navigating production mode in nuxtjs and uncovering errors

There seem to be numerous inquiries regarding this matter. Unfortunately, there doesn't appear to be a definitive solution. Is there any way to view detailed error logs in production mode? https://i.stack.imgur.com/prXUt.jpg ...

Issue with JSON data not functioning properly in AJAX request

I have been facing an issue with detecting whether a database entry has been successfully input. I am sending the new inserted ID and a JSON variable to an AJAX call, which works fine in all browsers but not in phonegAP. Despite that, the data is being suc ...

Is there a way to access a JSON node dynamically without relying on the eval function?

Path variables can be unpredictable, ranging from just a to a/b, and even a/b/c. My goal is to dynamically reach a node based on the path provided. The code snippet below achieves this, but I am open to exploring alternative methods that do not involve usi ...

Step-by-step guide: Uploading files with Ajax in Codeigniter

I am facing an issue with updating data and uploading an image when editing a row in my grid. Although the data is successfully updated, I am encountering difficulties in saving the image file to a folder. Here is what I have tried: While using AJAX, I ...

Sending a document to a distant server using a background script in Thunderbird

I am currently working on a Thunderbird extension that has the ability to upload attached files in emails. The process flow of this extension is outlined below: Clicking on the extension icon will display a popup with options to select from: "Read All", " ...

Error encountered: Attempting to access the 'length' property of an undefined variable in JSON data while using the $.each function

When I execute the following code snippet: var obj = $.parseJSON(json.responseText); $.each(obj.collection.response, function (i) { $.each(this.PRESENT_STUDENT, function (i, j) { $.each(j , function (i, j){ $( ...

Using the power of ReactJS, efficiently make an axios request in the

After familiarizing myself with Reactjs, I came across an interesting concept called componentDidUpdate(). This method is invoked immediately after updating occurs, but it is not called for the initial render. In one of my components, there's a metho ...

Utilize Multer to upload images stored within an array of objects

I've been having difficulty figuring out how to extract the images from an array of objects structured like this: import mongoose from "mongoose"; const prodcutSchema = new mongoose.Schema( { title: { type: String, require ...

Using jQuery to append content with a variable as the source

Recently delving into jQuery and encountering an issue with getting my variable inside src when using append. Either it's not functional at all, or just displaying the variable name in string form in the console. Here is the code causing trouble: va ...

What is the best way to exchange configuration data among Javascript, Python, and CSS within my Django application?

How can I efficiently configure Javascript, Django templates, Python code, and CSS that all rely on the same data? For example, let's say I have a browser-side entry widget written in Javascript that interacts with an embedded Java app. Once the user ...

Error: Unable to locate module: cannot find './node_modules/@material-ui/core/IconButton'

Encountering an error in the browser: Error: Failed to compile ./src/components/layout/search/Searchbar.js Module not found: Can't resolve './node_modules/@material-ui/core/IconButton' in 'C:\Users\Ja\Desktop\ ...

Error: Module not located - Unable to resolve 'crypto'

Upon running ng serve, I encountered a list of errors that need to be addressed. Here is my package JSON configuration: { "name": "ProName", "version": "0.0.0", "scripts": { "ng": "ng", "start": "ng serve", "build": "ng build", "tes ...