Solved

assigning an array

Posted on 1998-07-13
2
238 Views
Last Modified: 2010-04-01
i have an array class and i want to be able to initialize the array with a string of values or variable names, much like:

array<int> AnArray(6) = {1, 2, 3, 4, 5, 6};

or

array<int> AnArray(6);
AnArray.AssignArray(1, 2, 3, 4, 5, 6);

i have tried to do this but have the following problem.  if i made an AssignArray function it would have to take a variable number of parameters because different arrays have different number of elements.  i know overloading would take care of this but it would get tedious to make the same function over and over changing only the number of arguments, especially with arrays of hundreds of elements.  
do any of you know a better way to do this?
0
Comment
Question by:Booth882
2 Comments
 
LVL 11

Accepted Solution

by:
alexo earned 80 total points
ID: 1167620
There are several issues at work here.

First, a class can be initialized by an initialization list *only if* it does not have constructors, private or protected members, base classes, or virtual functions.

Second, a constructor (like any other function) can take a variable number of arguments.

For example:


    #include <stdarg.h>

    const int ArraySize = 5;

    class Array
    {
    public:
        Array(int, ...);

    private:
        int a[ArraySize];
    };


    Array::Array(int num, ...)
    {
        va_list args;
        va_start(args, num);
        for (int i = 0; i < num; ++i)
            a[i] = va_arg(args, int);
        va_end(args);
    }

    int main()
    {
        Array a(ArraySize, 1, 2, 3, 4, 5);

        return 0;
    }

Note however that no compile-time checking will be done on the arguments represented by the "..."
0
 
LVL 1

Author Comment

by:Booth882
ID: 1167621
thank you much!
0

Featured Post

Free Tool: Path Explorer

An intuitive utility to help find the CSS path to UI elements on a webpage. These paths are used frequently in a variety of front-end development and QA automation tasks.

One of a set of tools we're offering as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Many modern programming languages support the concept of a property -- a class member that combines characteristics of both a data member and a method.  These are sometimes called "smart fields" because you can add logic that is applied automaticall…
Basic understanding on "OO- Object Orientation" is needed for designing a logical solution to solve a problem. Basic OOAD is a prerequisite for a coder to ensure that they follow the basic design of OO. This would help developers to understand the b…
The goal of the video will be to teach the user the concept of local variables and scope. An example of a locally defined variable will be given as well as an explanation of what scope is in C++. The local variable and concept of scope will be relat…
The viewer will learn how to user default arguments when defining functions. This method of defining functions will be contrasted with the non-default-argument of defining functions.

679 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question