MrBuzzy.blog

Recently I was looking to store a ‘timespan’ in a config or ‘ini’ file. To store a truly configurable timespan I’d have to use a list (ie; cacheTime=0,0,2,0) and then programmatically split it up for use in the CreateTimeSpan function.

The ColdFusion docs say CreateTimeSpan returns a ’special’ date-time object. Experimenting with CreateTimeSpan, you can see it just returns numbers. These numbers when treated as a timespan or date have special meaning. But on their own they’re just numbers. So if I really wanted to, I could store these numbers in my config file. Yay.

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So what is a timespan? It’s a length of time (in days) represented as a decimal fraction. ie; 0.25 is a timespan of 6 hours.

CreateTimeSpan is simple (in a good way). You could even roll your own ‘MyCreateTimeSpan’;

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But is a timespan also a date? Yes, by default a timespan is also the number of days since December 29th 1899. ie; 0.25 is ‘6am on Dec. 30th 1899′.
Note: the timespan value does not contain a date as such. It’s just a number - a ‘numeric date’.

From the DateFormat documentation;
When passing date/time value as a string, enclose it in quotation marks. Otherwise, it is interpreted as a number representation of a date/time object.

Cool, so stuff like this is possible;
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So how can we create one of these numeric dates? Do we really want to? Not unless you’re a walking calendar who likes to write confusing code.
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Finally (it’s getting late), not all ColdFusion tags/functions can handle the numeric date. I guess that’s why we have IsNumericDate()…
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Thanks for reading. Enlightened or stricken with boredom?