[RESOLVED] can Global Variables be used in c#

[Sairan]

hi i'm trying to make a logic by using global variables.
i want to know that are their any global variables in c#??
if yes then i would like to know how to use them also
thanks

[MadHatter]

everything is encapsulated inside objects. that being the case, no there are no global variables in .net.

you can make "global" variables with a singleton object:

public class Global {
    // singleton implementation
    private static object syncLock = new object();
    private static Global instance;
    public static Global Instance {
        get {
            lock(syncLock) {
                if(instance == null) instance = new Global();
            }
             return instance;
        }
    }
    private Global() { 
        one = 1;
        two = false;
        er = 0.2F;
    }    
    // end singleton implementation
    private int one;
    private bool two;
    private float er;

    public int One { get { return one; } set { one = value; } }
    public bool Two { get { return two; } set { two = value; } }
    public Float Er { get { return er; } set { er = value; } }
}


// then anywhere in your app

Global.Instance.One = 7;


// somewhere else
int oneVal = Global.Instance.One;

[allholy1]

Wow... that's interesting. I'll use this too. Thanks

[bewa]

Wow Madhatter... that's a complicated way to do that. I always use this.

using System;

namespace Globals
{
	/// <summary>
	/// Summary description for Globals.
	/// </summary>
	public class MyGlobals
	{
    //NOTE:  THIS CONTRUCTOR IS PRIVATE, SO NO INSTANCES CAN BE CREATED
		private MyGlobals()
		{
		}

    //THESE MEMBERS ARE YOUR GLOBAL VARIABLES
    public static string Global1;
    public static int    Saucages_I_Have_Eaten;
	}
}

in your form, use the namespace Globals.

to set a global:

MyGlobals.Global1= "hello";

to read a global

string temp = MyGlobals.Global1;

[klintan]

If you search the net for singleton vs static you find there is a lot of debate about this.

First, globals should be avoided. But sometimes they simplify code, so...

Singletons are real objects, they can implement interfaces, be inherited, they can have state, you have more control of object creation.

Static members are simpler though.

[MadHatter]

also public static variables are not thread safe.

[wildfrog]

also public static variables are not thread safe.

Are public non-static variables of a singleton class/instance more thread-safe?

- petter

[MadHatter]

humor.