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Seb Nilsson

Display Local DateTime with Moment.js in ASP.NET

Moment.js

Displaying a DateTime in local format in C# is relatively easy, but it will only use the server's settings to tell what "local" is.

For example, you might want 2016-03-07 14:35 UTC to show as 2016-03-07 15:35 for a visitor from a CET-timezone.

If you want to dynamically show the local date and time you can use the web-client's information through JavaScript and format it with Moment.js, for any user, anywhere in the world.

To do this in a way that is fault-tolerant and also SEO-friendly I want the UTC-DateTime to be hard-coded in the HTML and let Moment.js format it on the fly, when the page loads. To do this I need to populate my .cshtml-file with the following:

<span class="local-datetime"
        title="@(Model.DateUtc.ToString("yyyy-MM-dd HH:mm")) UTC"
        data-utc="@(Model.DateUtc.GetEpochTicks())">
    @(Model.DateUtc.ToString("yyyy-MM-dd HH:mm")) UTC
</span>

Make sure you run .ToUniversalTime() on your DateTime first.

Notice the .GetEpochTicks()-extension method. It makes sure the format of the DateTime is passed in a format that Moment.js can handle easily. The implementation looks like this:

private static readonly DateTime Epoch = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);

public static double GetEpochTicks(this DateTime dateTime)
{
    return dateTime.Subtract(Epoch).TotalMilliseconds;
}

The last step is to tell Moment.js to format our DateTime to a local format:

$('.local-datetime').each(function() {
    var $this = $(this), utcDate = parseInt($this.attr('data-utc'), 10) || 0;

    if (!utcDate) {
        return;
    }

    var local = moment.utc(utcDate).local();
    var formattedDate = local.format('YYYY-MM-DD HH:mm');
    $this.text(formattedDate);
});

If this (or other, unrelated) JavaScript-code would fail for any reason the UTC-DateTime is the actually HTML-content and will still be displayed.

ViewSource - View Source in Mobile Browsers

ViewSource Screenshot

Here's another small app that I created to play around with some code, but mostly because I felt I had a need for it.

ViewSource is an app for viewing the HTML-source of any website from your web-browser. Which enables you to view source from mobile browsers.

Just enter any URL and view the HTML-source. You also get a list of CSS-files and JavaScript-files, which you can view the source of, instantly in your browser.

You can quickly reach the app through bit.ly/vsource.

Fork on GitHub

As always, the source is available on GitHub for forking.

Create Human-Readable File Size Strings in C#

After needing functionality in C# for getting a human-readable file-size string I posted a question about it on Stackoverflow, as one does.

The accepted answer had about 72 lines of code. One explanation for this could be that I did specify that I wanted the solution to implement IFormatProvider. Not sure why I did that, probably seemed right at the time, in the end of 2008.

One creative solution was to use a Win32 API call to StrFormatByteSizeA

[DllImport("Shlwapi.dll", CharSet = CharSet.Auto)]
    public static extern long StrFormatByteSize(long fileSize, [MarshalAs(UnmanagedType.LPTStr)] StringBuilder buffer, int bufferSize);

Compact, clean, cross-platform solution

For the sake of simplicity, readability and the bonus of cross-platform I re-implemented an earlier solution I found, that was written in JavaScript. But the solution was easily translateble into C#.

public static class FileSizeHelper
{
    private static readonly string[] Units = { "B", "KB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB" };

    private static string GetReadableFileSize(long size) // Size in bytes
    {
        int unitIndex = 0;
        while (size >= 1024)
        {
            size /= 1024;
            ++unitIndex;
        }

        string unit = Units[unitIndex];
        return string.Format("{0:0.#} {1}", size, unit);
    }
}

Squishify - Minify JavaScript & CSS Online

Squishify Screenshot

Squishify was created out of the need of a minifier for JavaScript. I quickly put together a web-app on AppHarbor to make minification always available quickly. The code is hosted on GitHub.

The application is an ASP.NET MVC-app, using Justin Etheredge's framework for minification called SquishIt. The app also uses ASP.NET Web API together with some simple jQuery to display the results of the minifications without any page-reloads.

The SquishIt-framework is a very easy to use and provides multiple minifiers for both JavaScript and CSS.

JavaScript minifiers:

* At the moment of writing this post, Google Closure is not working as expected, but should hopefully work soon.

CSS minifiers:

Enjoy it at squishify.apphb.com and fork it on GitHub.

jMapMarker - jQuery-Plugin to Easily Add Google Maps with Markers to Your Website

jQuery

Just uploaded my new project called jMapMarkers to GitHub.

It's a jQuery-plugin that easily allows the user to add one or more Google Maps-maps with markers and info-windows to the website.

It uses a simple object-literal as an argument for configuration when calling. To add a map to a div-tag with and ID, simple use the following code:

$('#map-placeholder').jMapMarkers({
    mapOptions: { // Straight Google Maps API-configuration
        zoom: 1,
        mapTypeId: google.maps.MapTypeId.ROADMAP,
        mapTypeControl: false
    },
    markers: [
        { lat: '59.329444', long: '18.068611', title: 'Stockholm', desc: 'Capital of Sweden' },
        { lat: '59.949444', long: '10.756389', title: 'Oslo', desc: 'Capital of Norway' }
    ]
});

You can even add on more markers after the initial map has been added. Just leave out the mapOptions-argument in the configurations-arguments, like this:

$('#map-placeholder').jMapMarkers({
    markers: [
        { lat: 52.500556, long: 13.398889, title: 'Berlin', desc: 'Capital of Germany' },
        { lat: 48.8567, long: 2.3508, title: 'Paris', desc: 'Capital of France' },
        { lat: 51.507222, long: -0.1275, title: 'London', desc: 'Capital of England' }
    ]
});

You can find examples in the demo.html-file in the GitHub-project.

A big bonus-feature is that if you don't state otherwise the plugin will automatically zoom and move the map so that all markers are visible, after markers are added to the map.

As it say in the GitHub-README: please feel free to fork and/or give feedback.