CODEWITHSUNDEEP
c#asp.netvariablesstatic
user2336491
user2336491

Reputation: 47

static variable ASP.NET

in asp.net web application if I want to store variable in a static object is that right? I don't want that this object will share its value with another request.

public static object Objects
{
    get
    {
        if (HttpContext.Current.Items["Objects"] != null)
            return (object)HttpContext.Current.Items["Objects"];
        else
        {
            HttpContext.Current.Items["Objects"] = new object();
            return new object();
        }
    }

    set { HttpContext.Current.Items["Objects"] = value; }
}

THX

Upvotes: 0

Views: 2744

Answers (5)

Steven
Steven

Reputation: 172606

Static fields are shared across the whole AppDomain. This means that ALL requests in a ASP.NET web application will use the same value and you will have to make sure that variable is thread-safe. If this is not what you want, consider the following:

  • Storing the value in the user session: HttpContext.Current.Session
  • Storing the value in the request: HttpContext.Current.Items. This way the value is cached throughout the current request, but not shared across requests.
  • Don't store the value at all.

In your case however, you are using a static property. This static property maps in your case to the HttpContext.Current.Items, which means that each request automatically gets its own variable and variables are not shared.

In other words, your code is thread-safe.

Upvotes: 3

Ty Petrice
Ty Petrice

Reputation: 1839

There are 4 main server Dictionary objects that store values between requests. Application - shares values between all requests and users. Cache - shares values between all requests and users but can be invalidated without restarting application. Session - shares values between requests within the same session, all pages share the same session object, and is user specific. ViewState - shares values between request but is page specific and user specific.

Upvotes: 0

RaulMonteroc
RaulMonteroc

Reputation: 186

if you want the benefit of static across a single request. That is, have a single request have access to the same value. Use a session variable instead.

Session['variable'] = value

this will store the value in the current session, this way you will have a different value per request.

Upvotes: -2

Tim Schmelter
Tim Schmelter

Reputation: 460018

If you want to use a static variable without sharing it across all requests you could store a session variable in a static property. Use HttpContext.Session to access it.

public static object Objects  
{
    get
    {
        if (HttpContext.Current.Session["Objects"] != null)
            return (object)HttpContext.Current.Session["Objects"];
        else
        {
            var obj = new object();
            HttpContext.Current.Session["Objects"] = obj;
            return obj;
        }
    }

    set { HttpContext.Current.Session["Objects"] = value; }
}

However, you should not return object but the correct type, that will increase readability, prevents exceptions and avoids always casting it where you use it.

Upvotes: 1

Adil
Adil

Reputation: 148110

I don't want that this object will share its value with another request.

You should not make it static then.

Upvotes: 1

Related Questions