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Issue: 13.3 (May/June 2015)
Author: Marc Zeedar
Author Bio: Marc taught himself programming in high school when he bought his first computer but had no money for software. He's had fun learning ever since.
Article Description: No description available.
Article Length (in bytes): 12,895
Starting Page Number: 67
Article Number: 13306
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13306.zip Updated: 2015-05-18 09:57:47

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Excerpt of article text...

Last issue I wrote about class extensions as a way to become a Xojo power user. Today I'm going to explore a topic that few talk about, but one that is really powerful. Let's explore custom operators.

Comparing Objects

It's a very common thing to store data as objects. For instance, if you're writing an address book type of program, you might create a personClass object with that person's name, address and other details inside it.

What often happens when you start with data this way is that eventually you find a need to compare those objects. Is Object1 the same as Object2?

Xojo isn't very good at telling you this. You might think you can write if object1 <> object2 then but that won't do what you want it to do. That's because Xojo compares its internal reference to the object, not the object contents.

You can think of the reference as a unique, internal ID. So Object1 might have an ID of 7 and Object2 might have an ID of 19. To Xojo, they'd be different, even if they contained the exact same data.

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