Dynamic arrays in visual basic - do they exist?

[VaxoP]

Anyone know?

for example, how can i add items to a string array, without defining a size?

i hate having to redim preserve string (ubound(string) + 1) for each and every item i add to it... and it just seems that for thousands of items, this would be slow (btw i dont know know how many items to add - i just parse data and add them as they come along)

Also, how can u 'clear' an array?

[dglienna]

I don't know if it will slow you down at all, but you may want to use a collection or a class instead of an array.

To clear an array, use

ERASE MyStringArray

[VaxoP]

I don't know if it will slow you down at all, but you may want to use a collection or a class instead of an array.

To clear an array, use

ERASE MyStringArray

i think collections are even slower than arrays.. and i dont know about clases

[Thief_]

If you are "sometimes" adding data to an array,

redim preserve string (ubound(string) + 1)

will be OK. But if you are adding lots of data all the time, test the ubound(string) with the current index of the array for which you want to add data to, and if it's close, add another 500.

redim preserve string (500)

[RhinoBull]

Anyone know?

for example, how can i add items to a string array, without defining a size? ...

You can't.

[pnish]

If you are "sometimes" adding data to an array,

redim preserve string (ubound(string) + 1)

will be OK. But if you are adding lots of data all the time, test the ubound(string) with the current index of the array for which you want to add data to, and if it's close, add another 500.

It's been my experience that ReDimming in large chunks is actually slower than ReDimming by 1 as required. It may have something to do with the way VB grabs memory and this would get worse as available memory dropped or if available memory was fragmented.

If you're interested, check this post for some discussion on the pros & cons of using Redim Preserve and arrays versus collections.

http://www.vbforums.com/showthread.php?t=246059

[Thief_]

Good reference Pete! Thanks.