asked on

VB.Net -> C# translation -- Array declaration

This is stupid ... but ... how does the following line of VB.Net translate into C#?

Private SeparationColors(MAX_COLORS) As System.Drawing.Color

(MAX_COLORS is Private Const MAX_COLORS As Byte = 25 which I've translated just fine.)

Thanks!

//I tried:
       private System.Drawing.Color[MAX_COLORS] SeparationColors;
//but got
//Array size cannot be specified in a variable declaration (try initializing with a 'new' expression)	
 
 
 
        private System.Drawing.Color[] SeparationColors;
        SeparationColors = new System.Drawing.Color[MAX_COLORS];
//but got 2 additional errors.
 
 
        private fixed System.Drawing.Color[] SeparationColors[MAX_COLORS];
//but got
//Fixed size buffer type must be one of the following: bool, byte, short, int, long, char, sbyte, ushort, uint, ulong, float or double

Open in new window

ASKER CERTIFIED SOLUTION

Cebik

membership

This solution is only available to members.

To access this solution, you must be a member of Experts Exchange.

Start Free Trial

Cebik

class a
{
    private System.Drawing.Color[] SeparationColors;
 
    public a()
    {
        SeparationColors = new System.Drawing.Color[MAX_COLORS];
    }
}

Open in new window

Daniel Wilson

ASKER

I knew I was missing something simple!

Thanks!

Fernando Soto

Try it like this:

private System.Drawing.Color[] SeparationColors = new System.Drawing.Color[MAX_COLORS];

CuteBug

This should work

Make sure that you have defined MAX_COLOR as int.

int MAX_COLOR = 256;
System.Drawing.Color[] arrColor = new System.Drawing.Color[MAX_COLOR];

Open in new window

Cebik

Hi ;)

class a
{
    private const byte MAX_COLORS = 25;
    private byte[] SeparationColors = new byte[MAX_COLORS];
 
    public a()
    {
    }
}

Open in new window

tculler

The above obviously works, but there's really no explanation there.

In C#, the array declaration is considered part of the object's "type". For example, unlike VB and C++, we must say

int[] someArray

instead of

int someArray[]

Also, the arrays are, by default, initialized to "null" ("Nothing" in VB). So, the declaration

System.Drawing.Color[] myColors;

is the same as saying

System.Drawing.Color[] myColors = null; // Nothing, no colors in the array

However, if you do initialize your array, you MUST give the size (this is the downside of arrays all around). For example, the following is NOT valid:

System.Drawing.Color[] myColors = new System.Drawing.Color[];

The second set of brackets must contain a positive integer value, no matter what.

The "fixed" keyword in C# has an entirely different meaning than in other languages--it has to do with pointers, and basically "pinning" them so the GC doesn't run off with the object.

Hope I helped,
Nate

Cebik

it's working checked

class a
{
    private const byte MAX_COLORS = 25;
    private System.Drawing.Color[] SeparationColors = new System.Drawing.Color[MAX_COLORS];
 
    public a()
    {
    }
}

Open in new window

cauos

private System.Drawing.Color[] SeparationColors = new System.Drawing.Color[MAX_COLORS];

Cebik

@tculler:

Thanks ;)
I don't speek english very well, thats why there was no explanation

VB.Net -&gt; C# translation -- Array declaration

VB.Net -> C# translation -- Array declaration