Programming help

[supamario00]

I just need some clarification

1. Will a variable defined in a subprogram be usable with that same string/data in the main or another sub?

2. Do I write a bunch of subprograms to monitor each conceivable error, one sub to monitor the whole thing, or a separate program altogether?

I have been reading my Beginning Programming for Dummies book and I just got to the section about Arrays. The book teaches you the basics of LibertyBASIC, REALBasic, Revolution, and C++.

a list of what I know now:

• PRINT
• PROMPT
• FOR-NEXT loops
• WHILE-WEND loops
• FUNCTIONS
• Subprograms
• ARRAY (kind of)
• and how to comment

Ill add more if I think of any

EDIT- I lost the CD with all the compilers on it soooo I have no way of writing anything other than C++ right now.

[Tim]

For both questions, the answer is the same: It depends

When you develop something, you literally create life in the form of the program. How you create that is up to you. There are probably a million ways to output "Hello World" if not more.

[Nghtmr9999]

Hmm, we'll see if I'm interpreting this correctly, and I'll do the best I can to explain it in "beginner speak"

By 'subprogram' I assume you mean a subroutine/method/function. If that's the case, then no, you cannot access a variable in another method. It will be out 'scope'

The way around this would be to pass in the value where you need it.


Lets say this is the method you want to access the value of some variable i.

(1)

public int myMethod(int i)
{
    System.out.println(i); //prints out i
}

This method takes in an integer "i" and prints it out.

To call this method, you would type...

(2)

    int myInt = 5;
    myMethod(myInt);

By doing this, you pass in a value to a variable to use in that function.

Let me expand a bit by adding more to method (1)

public int myMethod(int i)
{
    System.out.println(i); //prints out i
    int add = i+i;
    int sub = i-i;
    int mult = i*i;

    System.out.println(add); //prints out i+i, or 5+5. 10
    System.out.println(sub); //prints out i-i, or 5-5. 0
    System.out.println(mult); //prints out i*i, or 5*5. 25
}

As for your second question, most (good) compilers will catch programming errors for you. I would highly recommend Visual Studio's line of programs. As for runtime errors... write working code in the first place


If I need to elaborate more, let me know.

[supamario00]

Originally Posted by Nghtmr9999

As for your second question, most (good) compilers will catch programming errors for you. I would highly recommend Visual Studio's line of programs. As for runtime errors... write working code in the first place
.

I meant that when I'm writing a program and its all running, the message to display if an error occurred, how do I monitor those possible errors across the whole program

[Nghtmr9999]

you would want to use try/catch statements

try
{
    //do code stuff here
}
catch (Exception e)
{
     //output error message here
}

[supamario00]

Originally Posted by Nghtmr9999

you would want to use try/catch statements

try
{
    //do code stuff here
}
catch (Exception e)
{
     //output error message here
}

hehe not that far along in the book yet :P ill probably be there in the next two hours or so.