Array of an Object

[codeamin]

Hello there, I have a Requirement class. I wanted to instantiate a number of objects of the same class. So I created a array of Requirement object. Here is what I had: dim req() as Requirements Private sub CreateRequirements(num as Integer) for i as integer=0 to num req(i) = new Requirements next end sub Above code gives an error like "Object reference not set to an instance of an object". Can someone help me out? Thank you, Bashar Amin Sr. Software Engineer

[MohammadAmiry]

You should Redim the array first:

dim req() as Requirements

Private sub CreateRequirements(num as Integer)
Redim req(num) as Requirements
for i as integer=0 to num
req(i) = new Requirements
next

end sub

[codeamin]

Thank you. It solves the problem but does not need "as Requirements" for the Redim statement. I have another question. If you do not know the size at a time and I want to create the Requirement object dynamicly, do I need the Redim statement? Bashar Amin Sr. Software Engineer

[Qhalis]

Just curious: Do you have a hard reason why you need to use an array as opposed to an arraylist? It would handle all the resizing issues for you and, if needed, you can always generate an array from the ArrayList using ToArray(). Q.

[AhClem]

This statement: dim req() as Requirements only declares a reference to an array of type Requirements. It doesn't instantiate it. You need to initialize the reference to an instance of an array of that type before you can start assigning values to it. Will