Transform the C# DateTime to LocalTime on the client side using JavaScript

Question

Transform the C# DateTime to LocalTime on the client side using JavaScript

Utilizing the Yahoo API on my server to retrieve currency information can be done through this link: Yahoo Currency API

This API provides me with both a Date and a Time, which I'd like to combine into a single DateTime object. This will allow me to easily convert it to the local time for clients.

To achieve this, I initially used the following code:

DateTime combinedDateTime = dateOnly.Add(timeOnly.TimeOfDay);

Now, my goal is to convert this combined DateTime to the client's local time using JavaScript.

I attempted to do this on the client side with the following code snippet:

var d = new Date(d + " UTC");
alert(d.toString());

Update: The value of 'd' is 2015-04-06T12:32:00.

However, upon testing this code, I encountered an error stating 'Invalid Date'.

javascript c#datetime

Answer 1

Answer №1

To correctly generate an ISO 8601 string from your code, follow these steps:

var d = new Date(d + "Z");

The image below shows the output in the Chrome debug console:

Another option is to ensure that the Z is added by your .NET code by setting the .Kind of your DateTime value to DateTimeKind.Utc.

For instance:

d = DateTime.SpecifyKind(d, DateTimeKind.Utc);

An even better approach is to parse it as UTC from the start.

string dateOnly = "4/6/2015";
string timeOnly = "11:32pm";

DateTime dt = DateTime.ParseExact(dateOnly + " " + timeOnly,
    "M/d/yyyy h:mmtt",
    CultureInfo.InvariantCulture,
    DateTimeStyles.AssumeUniversal | DateTimeStyles.AdjustToUniversal);

This method is considered the most secure. By parsing it as UTC initially, both the kind and the Z will be properly set.

Answer 2

To correctly generate an ISO 8601 string from your code, follow these steps:

var d = new Date(d + "Z");

The image below shows the output in the Chrome debug console:

Another option is to ensure that the Z is added by your .NET code by setting the .Kind of your DateTime value to DateTimeKind.Utc.

For instance:

d = DateTime.SpecifyKind(d, DateTimeKind.Utc);

An even better approach is to parse it as UTC from the start.

string dateOnly = "4/6/2015";
string timeOnly = "11:32pm";

DateTime dt = DateTime.ParseExact(dateOnly + " " + timeOnly,
    "M/d/yyyy h:mmtt",
    CultureInfo.InvariantCulture,
    DateTimeStyles.AssumeUniversal | DateTimeStyles.AdjustToUniversal);

This method is considered the most secure. By parsing it as UTC initially, both the kind and the Z will be properly set.

Answer 3

Answer №2

Give this a try... My assumption is that the Yahoo CSV is formatted in US format (m/d/yyyy)... If it's not, you'll need to adjust how the month and date are extracted in fixYahooDate function...

(function() {
    'use strict';

    String.prototype.pad = function(c, l) {
        return (new Array(l + 1).join(c) + this).substr(-l, l);
    };

    function fixYahooDate(aDate) {
        var match = /(\d?\d)\/(\d?\d)\/(\d+)/gi.exec(aDate);
        var m = match[1];
        var d = match[2];
        var y = match[3];    
        var sm = m.pad('0', 2);
        var sd = d.pad('0', 2);    
        var fixedDate = sm + "/" + sd + "/" + y;
        return fixedDate;
    }

    function fixYahooTime(aTime) {
        var match = /(\d?\d):(\d\d)(am|pm)/gi.exec(aTime);
        var h = match[1];
        var m = match[2];
        var a = match[3];
        var sh = h.pad('0', 2);
        var fixedTime = sh + ":" + m + ":00 " + a + " UTC";
        return fixedTime;
    }

    function YahooDateTimeToLocal(aDate, aTime) {
        var s = fixYahooDate(aDate) + " " + fixYahooTime(aTime);
        console.log(s);
        var dt = new Date(s);
        return dt;
    }

    var aDate = "4/6/2015";
    var aTime = "12:29pm";

    var localDt = YahooDateTimeToLocal(aDate, aTime);    
    console.log(localDt.toString());

}());

Answer 4

Give this a try... My assumption is that the Yahoo CSV is formatted in US format (m/d/yyyy)... If it's not, you'll need to adjust how the month and date are extracted in fixYahooDate function...

(function() {
    'use strict';

    String.prototype.pad = function(c, l) {
        return (new Array(l + 1).join(c) + this).substr(-l, l);
    };

    function fixYahooDate(aDate) {
        var match = /(\d?\d)\/(\d?\d)\/(\d+)/gi.exec(aDate);
        var m = match[1];
        var d = match[2];
        var y = match[3];    
        var sm = m.pad('0', 2);
        var sd = d.pad('0', 2);    
        var fixedDate = sm + "/" + sd + "/" + y;
        return fixedDate;
    }

    function fixYahooTime(aTime) {
        var match = /(\d?\d):(\d\d)(am|pm)/gi.exec(aTime);
        var h = match[1];
        var m = match[2];
        var a = match[3];
        var sh = h.pad('0', 2);
        var fixedTime = sh + ":" + m + ":00 " + a + " UTC";
        return fixedTime;
    }

    function YahooDateTimeToLocal(aDate, aTime) {
        var s = fixYahooDate(aDate) + " " + fixYahooTime(aTime);
        console.log(s);
        var dt = new Date(s);
        return dt;
    }

    var aDate = "4/6/2015";
    var aTime = "12:29pm";

    var localDt = YahooDateTimeToLocal(aDate, aTime);    
    console.log(localDt.toString());

}());

Transform the C# DateTime to LocalTime on the client side using JavaScript

Answer №1

Answer №2

Similar questions

Are ES6 arrow functions not supported in IE?

Is it possible to include a local directory as a dependency in the package.json file

Guide on how to retrieve the vertex information once an object is loaded using the ObjLoader in Three.js

Can I create interactive stacked shapes with CSS and/or JavaScript?

Highcharts - resolving cross-browser e.Offset discrepancies in mouse event detection on charts

What is the best way to reload DataTables using an ajax/error callback?

What is causing Puppeteer to not wait?

Echo command fails to work with location.href

Image Animation Using a Rotational Control (HTML/JavaScript/...)

Curious about the method of refining a list based on another list?

Exploring ways to create fresh arrays derived from the original array

Integrating Gesture Handling in Leaflet JS for two-finger scrolling enforcement

Having difficulty initializing dropdownlist upon page load

Turn off the animation for the modal popup extender

Adjusting package.json settings for an npm module

Using regular expressions in JavaScript, eliminate all characters preceding a specified final character

Using axios.spread() allows for caching of my API requests, a feature that is not available when

Show the value of a JavaScript object in VueJS

Create a nested array of subcategories within an array object

Leveraging flot in conjunction with NPM, React, and Node