Learning differences between Early Binding & Late Binding

[mc84excel]

I am trying to learn the important differences between using Early & Late binding. Below is a summary of what I have noted so far:

1. Reference Libraries: Early = Required, Late = Doesn't use (? see post by Kyle123)
2. Speed: Early = slightly faster, Late = slightly slower
3. Intellisense: Early = Uses, Late = Doesn't use
4. Compatibility: Early = Low, Late = High (? see post by Kyle123)

My questions:

1. Is there anything in the above summary that I have incorrect?
2. Is there any important difference not in the above summary that I should be including?
3. When using binding I am more concerned about compatibility for other uses (more than speed increase). Would it be an idea to write the code in Early (for Intellisense) then convert the code to Late after it is working correctly?

[AB33]

2.Speed: Early = 2x(?) faster, Late = slower

is debatable and do not think it is a good idea to generalise.

[Norie]

1. 3? Not really sure what Intellisense has to do with error-checking/debugging.

2. Constants missing when late-binding.

3. It think you'll find that a lot of people take that approach as Early allows Intellisense and constants.

[Kyle123]

Some libraries don't work properly with late binding - some features may not be available.

[mc84excel]

2.Speed: Early = 2x(?) faster, Late = slower

is debatable and do not think it is a good idea to generalise.

I confess that the concepts of Early & Late binding is something I have only recently started learning.

I read somewhere that the speed of Early binding is around twice as fast as Late binding. If that isn't correct, please instruct me as to what is the speed difference. I am open to corrections to my assumptions (which is why I started this thread).

[mc84excel]

1. 3? Not really sure what Intellisense has to do with error-checking/debugging.

2. Constants missing when late-binding.

3. It think you'll find that a lot of people take that approach as Early allows Intellisense and constants.

Thanks Norie.

1. Probably bad choice of wording on my part. Intellisense helps you detect misspellings when you write the code?

2. Could you please expand on this?

[mc84excel]

Some libraries don't work properly with late binding - some features may not be available.

Now I'm confused. My understanding was that Late binding didn't rely on having specific Reference Libraries being enabled in order to run the code - which makes Late much more compatible when compared to Early. Could you please expand on this statement (or provide a hyperlink to a web page covering this)?

[AB33]

Yes, you are right early is generally faster than late, but I would not put in quantitative measurement.

[mc84excel]

OK I'll update the OP for this. (Myself - when the speed increase is so small, I am more focused on compatibility).

[Kyle123]

Off the top of my head, consider:

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The above requires a reference to the MS HTML Object Library and IE9+. As you can see, the early bound object has access to the method, whereas the late bound does not. It isn't really a major issue, especially if you set minimum requirements for your workbook since nothing beats proper testing on different platforms - just something to bear in mind.

FWIW I rarely ever used late binding, since there was a set structure of software where the versions could be guaranteed. I mostly use late binding when replying to answers in forums since it gets the solution up and running more quickly without confusing posters.

[Andy Pope]

Even with early binding you need to ensure the recipient of the workbook has the required library/referenced file(s).

[AB33]

Useful link

http://peltiertech.com/Excel/EarlyLateBinding.html

[mc84excel]

As you can see, the early bound object has access to the method, whereas the late bound does not.

You lost me on that sentence. (I have only recently started learning Early/Late Binding)

[mc84excel]

Even with early binding you need to ensure the recipient of the workbook has the required library/referenced file(s).

Thanks. That reason is why I am leaning towards adopting Late Binding permanently.

(Except post #10 has got me worried :S )

[mc84excel]

Useful link

http://peltiertech.com/Excel/EarlyLateBinding.html

Handy. Thanks +1

[Kyle123]

You lost me on that sentence. (I have only recently started learning Early/Late Binding)

It isn't complicated, did you run the code? - It becomes immediately apparent when you do

[mc84excel]

It isn't complicated, did you run the code? - It becomes immediately apparent when you do

I hadn't. (Runs it). Yes I see a problem now.

You said this wasn't a major issue? How do you work around this (supposing you want to adopt Late Binding?)

[mc84excel]

I was leaning towards adopting Late Binding (to save relying on the right references enabled when sending code to other users) but now Kyle has raised doubts in my mind.

I am considering a slightly alternative approach - how does the below sound?

• Use Early Binding to write the code
• At start of Sub, have code to programatically check if tool reference library is available
• If lib unavailable, notify user and exit sub. (If available, programatically enable and cont. sub)

(Note I'd still prefer to adopt Late Binding but I'm concerned about post #10)

[Kyle123]

Well I suppose it depends how many external libraries you're looking at using. As long as your code is thoroughly tested there's no issue and problems like I demonstrated are likely to be pretty few and far between