Delphi Performance Tip

💡 Delphi Performance Tip: Using TObjectList vs TList the RIGHT way

One thing I still see in legacy Delphi codebases is misuse of collections — especially when it comes to memory management.

If you're working with objects, choosing between TList and TObjectList matters more than people think.

🔍 Key difference:

TList stores pointers only

TObjectList actually owns the objects (if OwnsObjects = True)

👉 Why this matters:

Using TList:

You must manually free every object

Easy to introduce memory leaks

Using TObjectList:

Automatically frees objects when removed or destroyed Cleaner and safer code

🚀 In large enterprise systems, especially legacy applications, small improvements like this can significantly reduce memory leaks and improve stability over time.

In my experience, careful memory management is still one of the biggest differentiators in maintaining long-running Delphi applications.

Curious — what are your go-to techniques for avoiding memory issues in Delphi?

#Delphi #ObjectPascal #SoftwareEngineering #LegacySystems #CleanCode