UDF: Convert ColdFusion Date to JavaScript Date Object

Posted by Dan on May 2, 2008 @ 1:43 PM

I had the need to convert a ColdFusion date/time stamp to a JS Date Object. I thought serializeJSON() function would handle this, but it turns out it treats CF date/time variables as strings. The toScript() function will convert CF variables to JS Date Objects—provided that the date/time variable is in ODBC format (i.e. {ts '2008-05-02 13:32:16'}.)

However, I wanted something that would work for anything that ColdFusion saw as a Date object, so I just whipped out this little 4 line helper function:

function jsDateFormat(date){
    if( isDate(date))    return 'new Date(#year(date)#, #(month(date)-1)#, #day(date)#, #hour(date)#, #minute(date)#, #second(date)#)';
    else return "null";
}

If ColdFusion doesn't see the date as a date object, then it'll set the date/time to "null". To use this function you just do:

<script type="text/javascript">
var today = <cfoutput>#jsDateFormat(now())#</cfoutput>;
</script>

This would then generate the following:

<script type="text/javascript">
var today = new Date(2008, 4, 2, 13, 32, 16);
</script>

Obviously this is pretty straightforward, but it's saved me a lot of repetitive typing today and simplified the readability of my code.

Categories: HTML/ColdFusion, Source Code

10 Comments

  • shag's Gravatar
    shag
    this is pretty cool. im not sure most people would want to subtract a month from the date. i'm pretty sure that would cause problems for january as well. not to mention you exclude december. very cool tool though.
  • Dan G. Switzer, II's Gravatar
    Dan G. Switzer, II
    @Shag:

    In the Date Object in JavaScript, the month ranges from 0-11, so you need to subtract 1 from the CF date (since it's from 1-12.) Trust me, the code is correct.
  • shag's Gravatar
    shag
    i guess thats what i get for having avoided javascript for all these years.
  • chris hough's Gravatar
    chris hough
    I wanted to take a few moments to say thank you for this article, it really helped me solve a recent development issue, have a great week.
  • Roman's Gravatar
    Roman
    How about going in the other direction, how can I send a JavaScript Date Object back to ColdFusion?
  • Dan G. Switzer, II's Gravatar
    Dan G. Switzer, II
    @Roman:

    The odds are you're wanting to do more than just data object to CF, but you can certainly use AJAX to send the date object to CF.
  • Roman's Gravatar
    Roman
    Actually, I am using AJAX, I just can't figure out how to send the data as an object instead of as a string, so I don't have to keep formatting it to go both ways.
  • Dan G. Switzer, II's Gravatar
    Dan G. Switzer, II
    @Roman:

    Serialize using JSON.
  • Roman's Gravatar
    Roman
    Can you be a little more specific? How do I serialize and desearlize the js date object? That's what I was trying to figure out...
  • Dan G. Switzer, II's Gravatar
    Dan G. Switzer, II
    @Roman:

    Just use a JSON helper library. It'll manage the conversion of the JS objects and convert them to the correct JSON string.

    See http://www.json.org/ for more information. (In newer versions of CF, there's native support for deserializing JSON using deserializeJSON().)

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