CODEWITHSUNDEEP
.netvariables
DarkW1nter
DarkW1nter

Reputation: 2861

.net global variable

whats the best way to set up a global variable that I can access thoughout a .net site. Basically I want to use it as a yes/no type of flag that I can refer to from any page.

thanks

Upvotes: 2

Views: 2396

Answers (8)

Jane
Jane

Reputation: 159

You can create a variable using Application Object.

Add the following code to the Application_Start event in the code-behind module for the Global.asax file:

Application("abc") = "hi"

Upvotes: 0

Mhmd
Mhmd

Reputation: 5177

yes as TakeMeAsAGuest said

make a class static have all you configuration values you want

public static class ProgramSettings
    {
        private static bool _flag = false;
        public static bool Flag
        {
          get { return _flag; }
          set { _flag = value; }
        }
    }

on application start set you properties as you want and read it from xml file or read it from web.config by adding in web.config

  <appSettings>
    <add key="flag" value="true" />
  </appSettings>

and read it in application_start like

using System.Configuration;    
ProgramSettings.Flag = ConfigurationManager.AppSettings["flag"]

My Regards

Upvotes: 0

jgauffin
jgauffin

Reputation: 101192

Since you say flag I would use a const since it prevents the bool from being changed anywhere in the code:

public static class ApplicationFlags
{
    public const bool MyFlag = false;
}


if (ApplicationFlags.MyFlag)
    Reponse.Write("Ohh, my!");

You could also use static fields. Please note that static fields are not thread safe. If you change them in one thread (one http request) it will also be changed for all other threads.

Upvotes: 1

Shadow Wizzard
Shadow Wizzard

Reputation: 66398

One way that wasn't described in detail yet (although mentioned) is using AppSetting value from the web.config file.

First, in the web.config file, under <configuration> add the following:

<appSettings>
    <add key="MyGlobalVar" value="true"/>
</appSettings>

The <appSettings> section might already exist, in such case just add the <add ... to it.

Second, to be able to read from it, add reference to System.Configuration assembly in your project.

Finally to read the value from any page, have such code:

string myGlobalValue = System.Configuration.ConfigurationManager.AppSettings["MyGlobalVar"];

You can then change the value in the .config file and saving it will make the web application "restart" as the pool will be recycled.

Upvotes: 3

FreeAsInBeer
FreeAsInBeer

Reputation: 12979

If you are wanting to store these per user and they may change periodically because the user performed some behavior then it may be best for you to use session variables.

VB:

Session("FirstName") = FirstNameTextBox.Text
Session("LastName") = LastNameTextBox.Text

C#:

Session["FirstName"] = FirstNameTextBox.Text;
Session["LastName"] = LastNameTextBox.Text;

You can store any reference or value types in the Session. Just remember that as long as these values persist, they are taking up RAM on the servers for any users that have these variables set.

If you want to store a global variable that is used for all users, then you could use global static variables.

If you already know the value and it's never going to change, then you could do something like:

static string ImportantData = @"Some String That Will Never Change";

Upvotes: 0

JCasso
JCasso

Reputation: 5523

You can use static keyword for that. Also i suggest you to check enumerations in c#

Upvotes: 1

TakeMeAsAGuest
TakeMeAsAGuest

Reputation: 995

its very simple question. you can create and set public static a bool variable anywhere you want. an example is:

public static class ProgramSettings
    {
        public static bool Flag = false;
    }

but if you want to change flag value without compiling, you may use configuration settings. (web.config)

Upvotes: 1

Darren Young
Darren Young

Reputation: 11100

Generally, global variables are kind of frowned upon, but if it fits into you design choices, then you can use a static class, with static members.

Upvotes: 2

Related Questions