Programming Forums > Application Development > C#

Twilight · Apr 25th, 2006, 2:48 AM

I'm using an Array list to hold a bunch of struct items, but I can't seem to get an insertion going.

struct FullItem
    {
        public String name;
        public int code;
        public int quantity;
        public double price;
        public double weight;
    }

. . .

private ArrayList Purchase = new ArrayList();

. . .

FullItem FullPurchase;
FullPurchase.code = purchase.Code;
FullPurchase.name = purchase.Name;
FullPurchase.price = purchase.Price;

if (purchase.ByWeight == true)
{
      FullPurchase.weight = 100 / 1000;  // add wieght input
      FullPurchase.price = FullPurchase.weight * FullPurchase.price;
}
            
      FullPurchase.quantity = 1; // add something for getting Q numbers

      Purchase.Add(FullPurchase);  //----this line has the error-------

. . .

Oddly enough, I inserted a different sturct item into a different ArrayList, with no problem, and I can clearly access members of FullPurchase, but the add line gives me the following error, wherever I put it:

(Toggle Plain Text)

Error	1	Use of unassigned local variable 'FullPurchase'

Suggestions?

Kaja Fumei · Apr 25th, 2006, 3:59 AM

Even though struct's are stored on the stack, they still need to be allocated and initialized with a call to new:

(Toggle Plain Text)

FullItem FullPurchase = new FullItem();

I'm surprised the errors didnt start on this line:

(Toggle Plain Text)

FullPurchase.code = purchase.Code;

Twilight · Apr 25th, 2006, 2:15 PM

Yeah, that did it. But It surprises me that I have another instance of this in a different program where I didn't use new and it worked fine

Apr 25th, 2006, 2:48 AM	#1
Twilight Programmer Join Date: Apr 2006 Location: Calgary, Alberta Posts: 67 Rep Power: 3	Problem with an ArrayList I'm using an Array list to hold a bunch of struct items, but I can't seem to get an insertion going. (Toggle Plain Text) struct FullItem { public String name; public int code; public int quantity; public double price; public double weight; } . . . private ArrayList Purchase = new ArrayList(); . . . FullItem FullPurchase; FullPurchase.code = purchase.Code; FullPurchase.name = purchase.Name; FullPurchase.price = purchase.Price; if (purchase.ByWeight == true) { FullPurchase.weight = 100 / 1000; // add wieght input FullPurchase.price = FullPurchase.weight * FullPurchase.price; } FullPurchase.quantity = 1; // add something for getting Q numbers Purchase.Add(FullPurchase); //----this line has the error------- . . . struct FullItem { public String name; public int code; public int quantity; public double price; public double weight; } . . . private ArrayList Purchase = new ArrayList(); . . . FullItem FullPurchase; FullPurchase.code = purchase.Code; FullPurchase.name = purchase.Name; FullPurchase.price = purchase.Price; if (purchase.ByWeight == true) { FullPurchase.weight = 100 / 1000; // add wieght input FullPurchase.price = FullPurchase.weight * FullPurchase.price; } FullPurchase.quantity = 1; // add something for getting Q numbers Purchase.Add(FullPurchase); //----this line has the error------- . . . Oddly enough, I inserted a different sturct item into a different ArrayList, with no problem, and I can clearly access members of FullPurchase, but the add line gives me the following error, wherever I put it: (Toggle Plain Text) Error 1 Use of unassigned local variable 'FullPurchase' Error 1 Use of unassigned local variable 'FullPurchase' Suggestions?

Apr 25th, 2006, 3:59 AM	#2
Kaja Fumei Hobbyist Programmer Join Date: Oct 2005 Posts: 134 Rep Power: 4	Even though struct's are stored on the stack, they still need to be allocated and initialized with a call to new: (Toggle Plain Text) FullItem FullPurchase = new FullItem(); FullItem FullPurchase = new FullItem(); I'm surprised the errors didnt start on this line: (Toggle Plain Text) FullPurchase.code = purchase.Code; FullPurchase.code = purchase.Code;

Thread Tools
Show Printable Version Email this Page
Display Modes
Switch to Linear Mode Hybrid Mode Switch to Threaded Mode

Apr 25th, 2006, 2:15 PM	#3
Twilight Programmer Join Date: Apr 2006 Location: Calgary, Alberta Posts: 67 Rep Power: 3	Yeah, that did it. But It surprises me that I have another instance of this in a different program where I didn't use new and it worked fine

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)

Programming Forums > Application Development > C#

Problem with an ArrayList