option buttons

hi vbguru

there r 2 opt butns with in a frame and 2 without a frame on design form here i want to select one among the
with in frame one from without a frame
give me suitable example

give me advtgs & disadvantage of collection s over arrayss
with example ?

[Reid Robbins]

You can, in code, select an option button regardless of whether it resides within or outside of a frame, by setting its "Value" property to "True". The within/without issue only dictates which other options buttons will be automatically switched to "False" when one of the group is clicked, or has its Value property set to true. Example:


MyButton.Value = true




will "click" the desired button no matter where it resides (inside a frame, or not).

As for collections vs. arrays, the difference is night and day: an array can only contain elements of a single type (though that type may be a user-defined data type containing an admixture of other data types), whereas a collection may contain ANY object (typically created by a class module) whatever. Examples:


Type MyType
Dim AnInt as Intger
Dim AString as string
End Type
private MyArray(1 to 100) as MyType
MyArray(5).AnInt = 5
MyArray(6).AString = "This is a string"




The above array can contain ONLY objects of type "MyType". Or, if the array was declared "As Integer", can contain only integers. Or, if "As String", only strings. Etc.
On the other hand, let us assume you have designed a financial statement (in OOP form). You may have created class modules to define objects of the classes "AccountLine", "HeaderLine", "BlankLine", "TotalLine", etc. Then, your financial statement could, conceivably consist of a collection of these different classes; each is different, with its own encapsulated data and methods. Yet the "Financial Statement" collection can hold them all. No examples here: it would take a lot of code to demonstrate. But, hopefully, the explanation will suffice.



Reid Allen Robbins
2205 E. Teton Blvd.
Green River, WY 82935

[Ravi Kiran]

Collections need not be Complex stuff with Financial statements :-)
Following the same example of UDT, you can make a collection like this:

dim pColectn as Collection
dim i as integer, szStr as string
set pColectn = new Collection
i = 4
pColectn.Add i ' Element 1 : Note Collections go From 1 to N
szStr = "Some string"
pColectn.Add szStr ' Element 2
i = 5
pColectn.Add i ' Element 3
' Note the difference here :
i = 6
pColectn.Add i ' Element 4
i = 7
pColectn.Add i ' Element 5
i = 8
pColectn.Add i ' Element 6
szStr = " string 2"
pColectn.Add szStr ' Element 7

for i = 1 to pColectn.Count
Debug.print pColectn.Item(i)
next i

set pColectn = nothing
'
'should give you a debug print of:
4
string 1
5
6
7
8
string 2



Suddenly, if you choose to: you can have something like:
dim pCls as SomeClass
set pCls = New Class
pCls.Prop1 = something ''.. and

pColectn.Add pCls ' for 7th Element!!!

That is the power of collections. It gives big enough rope...to hang oneself:-)

Simply said: An array is type of 'similar elements', while a Collection can contain a collection of vertually anything with what ever intermixing, incl regular types , classes etc.
But you cannot add an UDT to a collection, AFAIK.


RK

[wayne]

Arrays are faster than collections. The advantage of collections is that they can be added to with an id and selected using that id which makes collections simple to retrieve data (if stored with an id). Unless you need this then use arrays. Such as:
collection.Add Text1.Text, Id ==> where id = what you want to identify this by.
To retrieve the data for id use:
collection.Item("id")

A varient array can hold many different types and can be changed from string to integer to single, etc. They too are slow and take up more space then typed arrays. Such as:

Dim MyArray(10) as Variant
MyArray(1)="This is Text"
MyArray(1)=123 ==> Has changed text to an integer

Hope this rambling helps.