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[Bauglir]

Half the time it works like you think it should, the rest of the time it explodes and wipes half a planet from existance.

That's better than my usual success rate, so I'm seeing this as an improvement.

[Johuotar]

Hi all. I'm trying to spawn some people to my game view. I have array that should contain the references to the actor class but I cannot actually put object into the array, so all the values are null. Currently I have error messages about the objects I'm trying to put into the array. I'm kind of stumped here. Part of the problem is I don't know any c++ and I'm using tutorial in c++ so translating it to c# is difficult. Please help.


code

Spoiler (click to show/hide)

Code: [Select]

class ActorList
    {
        // This is array of all actors with max actors as its size.
        public Actor[] p_cActorList = new Actor[GlobalVar.MAX_ACTORS];
    }

Code: [Select]

ActorList actorlist = new ActorList();

            int i = 0;
            for (i = 0; i < GlobalVar.MAX_ACTORS; i++) // Initialize the actor list to be empty
            {
                actorlist.p_cActorList[i] = null;
            }

            Manager manager = new Manager(); //now moved out of while loop

            Actor actor = new Actor();

            Actor newActor;

            for (i = 0; i < GlobalVar.MAX_ACTORS; i++)
            {
                manager.AddActorToList(newActor); //THIS IS THE OFFENDING CODE!
                actorlist.p_cActorList[i].SetAppearance('@');
                actorlist.p_cActorList[i].SetPos(5, 5);
               
            }

Code: [Select]

public bool AddActorToList(Actor[] p_cNewActor)
        {
            // Run through the list looking for an empty slot
            int i = 0;
            for (i = 0; i < GlobalVar.MAX_ACTORS; i++)
            {
                // Is this empty?
                if (actorlist.p_cActorList[i] == null)
                {
                    // If so, use it!
                    actorlist.p_cActorList = p_cNewActor;
                    // Finished! Report success
                    return true;
                }
            }
            // Couldn't find a free slot. Report failure.
            return false;
        }

errors

Spoiler (click to show/hide)

Error   2   Argument 1: cannot convert from 'TowerAdventure.Actor' to 'TowerAdventure.Actor[]'   C:\Tower-Adventure\Tower Roguelike\TowerAdventure\TowerAdventure\Program.cs   48   40   TowerAdventure

Error   1   The best overloaded method match for 'TowerAdventure.Manager.AddActorToList(TowerAdventure.Actor[])' has some invalid arguments   C:\Tower-Adventure\Tower Roguelike\TowerAdventure\TowerAdventure\Program.cs   48   17   TowerAdventure

github link with all the code
https://github.com/Johuotar/Tower-Adventure

tutorial I'm using (article 8 )
http://www.kathekonta.com/rlguide/article8.html

[cerapa]

That tutorial should be thrown into the bowels of hell so that it may burn for an eternity and have its taint removed from this world.

EDIT:
The author is unaware of the existence of vectors and list.
The author is unaware of the existence of enums.
The author is concerned about the encapsulation of a boolean, while happily suggesting the use of an array of naked pointers.
The author keeps using this-> inside methods. (this one is just a nitpick)

As for the last criteria - Will This Make Me Want to Give Up Later On? - remember from previous articles, the number one challenge of programming is managing complexity..

Apparently the number one challenge is actually knowing the goddamn language features.

[Skyrunner]

Also, saying C/C++ then blatantly using classes.

[Telgin]

Heh, I've noticed that a lot of people have been cracking down on saying "C/C++" lately, especially at StackOverflow.  They've got a point too: the languages are almost nothing alike anymore.  I can't even decipher C++11 code half of the time, so I've all but given up on keeping up with the language in favor of writing C code if I absolutely must code in a compiled language, or older style C++ if I think I need OOP.  That basically amounts to manual memory management rather than smart pointers, STL containers and strings and very, very rare usage of templates.  I really should learn smart pointers...

Anyway, I'm not very experienced with C# as I've only fooled around with it a time or two, but I think your function should look closer to this:

Code: [Select]

        public bool AddActorToList(Actor p_cNewActor)
        {
            // Run through the list looking for an empty slot
            int i = 0;
            for (i = 0; i < GlobalVar.MAX_ACTORS; i++)
            {
                // Is this empty?
                if (actorlist.p_cActorList[i] == null)
                {
                    // If so, use it!
                    actorlist.p_cActorList[i] = p_cNewActor;
                    // Finished! Report success
                    return true;
                }
            }
            // Couldn't find a free slot. Report failure.
            return false;
        }

Your function's prototype was using [] notation, which means it was expecting an array of actors, but you wanted to only pass one to it.  I also fixed up actorlist.p_cActorList to use [] notation inside your loop, since it was trying to reassign the entire array instead of just one element of it.  Hopefully my brief scanning of it didn't completely miss the point of the function.

[Parsely]

Spoiler (click to show/hide)

1. Write a SQL script that adds an index to the my_guitar_shop database for the last_name field in the Customers table.
 
2. Write a script that implements the following design in a database named my_web_db:

- In the Downloads table, the user_id and product_id columns are the foreign keys. Include a statement to drop the database if it already exists.
- Include statements to create and select the database.
- Include any indexes that you think are necessary.
- Specify the utf8 character set for all tables.
- Specify the InnoDB storage engine for all tables.
 
3. Write a script that performs the following three activities on the database that you created in problem 2.

- Add two rows to the Users and Products tables.
- Add three rows to the Downloads table: one row for user 1 and product 2; one row for user 2 and product 1; and one row for user 2 and product 2. Use the NOW function to insert the current date and time into the download_date column.
- Write a SELECT statement that joins the three tables and retrieves the data from these tables like this:

Sort the results by the email address in descending sequence and the product name in ascending sequence.

 
4. Write a script that contains an ALTER TABLE statement that adds two new columns to the Products table created in problem.

- Add one column for product price that provides for three digits to the left of the decimal point and two to the right. This column should have a default value of 9.99.
- Add one column for the date and time that the product was added to the database.

 
5. Write a script that contains an ALTER TABLE statement that modifies the Users table created in problem 2 so the first_name column cannot store NULL values and can store a maximum of 20 characters.

Welp. This is what the book calls for. And suddenly with the introduction of scripting the amount of stuff I have to type is multiplied by 10 million. *sighs and gets to work*

[EnigmaticHat]

Hint to anyone doing anything:

When iterating through a list/map/vector with a for loop, do not change the list/map/vector from inside the loop. Half the time it works like you think it should, the rest of the time it explodes and wipes half a planet from existance.

It is a lesson I have had to learn many times, but somehow I always forget.

I hesitate to post in this thread because I'm just a Python baby, but have you tried iterating through the list backwards?  That's worked for me when I've needed to remove entries from a list while iterating through it.

[Orange Wizard]

Code: [Select]

list = stuff
newList = empty list
for thing in list:
    do_stuff()
    append thing to newList
list = newList


[Skyrunner]

But what if that list has 10 million elements? D:

[da_nang]

Parallelize it!

[Orange Wizard]

Make smaller lists? Get more RAM?

[Sergius]

Don't add/remove items to the list until you're finished looping. Defer it for after.

[Orange Wizard]

How would that work?

[Skyrunner]

Find a way to track all the elements you need to remove, then after you get a list of elements to remove, do that.

[Johuotar]

-snip-

Thanks Telgin, I've made more progress now that got fixed. The code isn't perfect yet but you were of much help.