Jon Hartmann - ColdFusion

Why IIF() Should be Avoided

Mon, 17 May 2010 11:37:00 -0500

I was recently reviewing some code from one of my client projects and saw that the previous developer had liked to use IIF() functions to handle the conditional switching of things like button labels. I idly quipped on Twitter that Every time you execute IIF() an angel loses its wings. A few minutes later a request for some explanation came in on Facebook: Why's that? I like IIF(). Here is why you should avoid IIF(). [More]

Utility Function: ImageBlurMore()

Fri, 26 Mar 2010 08:46:00 -0500

OK, so up until now you probably can guess that the functionality I'm working on has something to do with drawing or moving a shape since I've posted math rounding functions and functions dealing with geometric positioning. Lets throw you a curve-ball: I also need the following function. What happens when ImageBlur(image, 10) just isn't enough? Well you're going to need to blur the image more! [More]

Utility Functions: Geometry Functions

Wed, 24 Mar 2010 22:16:00 -0500

Today we've got a double header of functions dealing with Geometry. As I said in my last post, I've been spurred into action by a user's question, and in order to solve his problem, I'm going to need to be able to calculate some relatively simple geometry. Click "more" to see how to convert Degrees to Radians and how to calculate the position of a point based on a starting location, angle, and distance. [More]

Utility Function: RoundToClosest()

Mon, 22 Mar 2010 22:04:00 -0500

Its been a while! I got an email from a reader who wanted some help with a bit of image manipulation that has roused me back into CF coding! The particular bit of functionality he wants is rather complex, and so its been forcing me to make a bunch of utility functions to piece it together. First thing I ran into: rounding a number in CF is a little tricky. If you want to round to 2 decimal places, you should multiply the number by 100, call Round() and then divide by 100 again. What a waste. Luckily a little trickery with NumberFormat() can get us what we want. [More]

How Do You Do This with ColdFusion 9 ORM ?

Wed, 25 Nov 2009 18:35:00 -0500

OK, so I've been working through build a new blog platform using the new ColdFusion 9 ORM setup, and I'm really impressed with how much of the basics it handles for you, but I'm starting to get into stuff thats more than just a simple CRUD action, and I'm finding that I've no idea how to make the ORM or HQL get me the results I need. Perhaps you can help me figure out what I need to do. [More]

Weird ColdFusion 9 ORM Error

Tue, 27 Oct 2009 17:32:00 -0500

I'm trying to get a feel for the new ColdFusion 9 ORM setup, and I ran into an error message that I'd not seen before stating that "[Macromedia][SQLServer JDBC Driver][SQLServer]'FK3498A0CE621DF1' is not a constraint." This isn't too daunting, since I'm used to weird SQL errors, but when I refreshed the error I got back "[Macromedia][SQLServer JDBC Driver][SQLServer]Cannot find the object "post" because it does not exist or you do not have permissions." instead.Take a look at the particulars, and see if you can help me out. [More]

ColdFusion Snippet Stumper

Fri, 16 Oct 2009 10:37:00 -0500

I ran across this bit of CF code in a project that I'm working on upgrading, and I was so completely confused by the it that I thought I might throw it up here to see what people think of it. [More]

IE Forgets Cookies on Sub-Domains with an Underscore

Wed, 23 Sep 2009 08:49:00 -0500

Ok, so one more reason to hate IE: Internet Explorer fails to hold cookies when viewing URLs that have a sub-domain with an underscore. I found this when the project I'm developing just refused to hold on to a session when viewing the site from Internet Explorer. Almost all of the server-side technology I was using was new to me, so I lost a full day trying to figure out if it was ColdFusion 9, IIS7, or the ColdFusion on Wheels framework that was breaking the sessions before I found out that the IE browsers choke on underscores. FireFox and Chrome didn't care about the underscore, but IE6 through IE8 lost their session because they couldn't hold onto the cookies for the site. So, if you're loosing your sessions in Internet Explorer, check your URL. I'm not sure if there are other characters besides an underscore that would cause the cookie loss, but it wouldn't surprise me.

Installing ColdFusion on IIS7 Still a Pain

Thu, 03 Sep 2009 13:30:00 -0500

This post isn't anything new, but I felt that I should document that yet another person has wasted some of their life struggling to get CF working on an IIS7 machine. I first ran into this problem about 6 months ago when trying to install CF8 on Windows Server 2008 (64-bit), and we had so many problems doing it that the server was rolled back to Windows Server 2003 (32-bit) to get around it. Today I had to get CF9 installed on a Vista, and had to deal with the same issues all over again. Luckily the solution was simpler this time, and involved only one reinstall of CF, rather than 5 and a full wipe of an OS like last time. Why hasn't this been fixed by now? Oh, and for those needing a solution, I found mine at Dale Fraser's Blog.

ColdFusion Instance Issues, Round 2

Mon, 01 Jun 2009 15:57:00 -0500

As some of you might know, my work place is no stranger to odd server problems, such as instances just wanting to return 503 errors. Today I have a new one: one of our applications refuses to run at full speed if its in anything other than the default instance. [More]

Using ColdFusion to Zip Individual Files

Thu, 28 May 2009 10:43:00 -0500

I ran into an interesting situation this morning that didn't have an obvious answer. I needed to create a zip with a few specific files out of a directory with lots of possible files. The problem is that <cfzip /> is designed to work against whole directories, so at first I kept thinking that I'd have to make a temporary directory, move the files to it, and then zip the directory, but a little more persistence found the right answer. [More]

Building Pages with a Page Object

Wed, 20 May 2009 23:34:00 -0500

I was reading through PHP and MySQL Web Development at the local bookstore the other night when I noticed that their example code for explaining object oriented concepts was a Page class that basically built a page based on its properties. While the concept of directly building the return code string by string is a little foreign to ColdFusion, I was very interested in the idea of an extensible Page object that could help me manage my applications. Read more to see what I came up with. [More]

Functions at CFLib.og

Tue, 19 May 2009 05:30:00 -0500

Three of my functions have made it onto CFLib.org. These probably aren't new to you if you've been following by blog, but since I don't think there is anyone watching me that close, check out GetSecureURL(), IsColor(), and IsSQLServerDate() at CFLib.org. While you're there check out some of the many awesome functions that other people have submitted too.

Object-Oriented Value Caching

Thu, 14 May 2009 16:30:00 -0500

Like every other developer out there, I often find myself repeating the same kind of functionality over and over again, and like every other programmer (or at least a lot of you), I apply the DRY principal and abstract it away into a function for reuse. Recently though, I've noticed that its not just specific bits of code that I'm reusing, but patterns for performing actions, and I've wanted to start looking for better solutions. [More]

Session Is Invalid Error

Fri, 08 May 2009 13:29:00 -0500

I first got this error a few weeks back, and when it showed up again this week, I thought I should look into it and see how this could be happening, and I thought that I'd post the results here so that it might aid the next person trying to stitch together the details. [More]