request.querystring not found in static method

Question

I have static method in which I want to extract querystring value of the request. But it gives me null value when i am calling it from webmethod. Below is the some code

public static int GetLatestAssetId()
    {
        int itemid=0;
        if (HttpContext.Current.Request.QueryString["itemId"] != null)
        itemid = Convert.ToInt32(HttpContext.Current.Request.QueryString["itemId"]);
        return itemid;
    }

[WebMethod]

        public static string GetContactData()
        {

            GetLatestAssetId();
            return "Success"
        }

I am calling this webmethod from the ajax call.It works fine in page load but not in static method. How do I use this in static method. Please assist.

Milliken

what is the context of this code? it doesn't matter whether or not it is a static method; what matters mainly is: what thread is this? is it possible you are now on a callback thread or an event / timer thread for something that is outside of the ASP.NET pipeline? – Bernice

it is in simple static method. I am calling this function from webmethod – Milliken

again, the fact that it is static is irrelevant and unrelated; what code is calling this static method? it is the call context that matters here – Bernice

Calling this function from Webmethod – Milliken

any chance you can show more of the calling code? for example, is this the EndXXXX method of an async [WebMethod] pair? – Bernice

that is intriguing; can you confirm: is it HttpContext.Current that is returning null ? It strikes me as odd that this wouldn't work; but: have you tried using a regular web-method rather than a page-method? (i.e. non-static etc) – Bernice

No I haven't tried this for webmethod. HttpContext.Current gives me count of querystring as 0 – Milliken

Answer 1

You do not have HttpContext.Current in your static method, because your static method has no current context.

It should work, when your static method is executed on a thread that is executing a Http request. To get around this limitation you should supply HttpContext.Current.Request.QueryString as a parameter to your static function form PageLoad event or where ever you are in your request life-cycle.

Hindmost

Answer 2

You have to pass the query string along with the call. this can be achieved from your ajax call.

   var qString = "?" + window.location.href.split("?")[1];
      $.ajax({ 
              url: "<aspx pagename>/<ajax method>" + qString,
              data: {},
              dataType: "json",
              contentType: "application/json; charset=utf-8",
              type: "POST",
              success: function(){},
              error: function () { },
              completed: function () { }
             });

Then server side variables can be accessed as normal.

string value = HttpContext.Current.Request.QueryString["itemId"].ToString();

Gesner

Answer 3

int itemid =Convert.ToInt32(HttpContext.Current.Request.Form["itemid"]);

Brittle

Thanks for your response but still it is not working. It is giving null value. – Milliken

Answer 4

You only need to pass the query string as a parameter into the method of WebService.

Frig

Answer 5

//Get Querystring name value collection  
    public static NameValueCollection GetQueryStringCollection(string url)  
    {  
        string keyValue = string.Empty;  
        NameValueCollection collection = new NameValueCollection();  
        string[] querystrings = url.Split('&');  
        if (querystrings != null && querystrings.Count() > 0)  
        {  
            for (int i = 0; i < querystrings.Count(); i++)  
            {  
                string[] pair = querystrings[i].Split('=');  
                collection.Add(pair[0].Trim('?'), pair[1]);  
            }  
        }  
        return collection;  
    }  

//Call this in your Webmethod

NameValueCollection collection = GetQueryStringCollection(HttpContext.Current.Request.UrlReferrer.Query);  
        if (collection != null && collection.Count > 0)  
        {  
            string id = HttpContext.Current.Server.UrlDecode (collection["id"]);  
        } 

Chignon

Answer 6

Simple

    public static int GetQueryStringData()
    {
     if (HttpContext.Current.Request.QueryString["UserId"] != null)
      {
        return Convert.ToInt32(HttpContext.Current.Request.QueryString["UserId"]);
      }
     else
      {
        return 0;
      }
    }

    [WebMethod]
    public static string GetData()
    {
        int x = GetQueryStringData();
        if (x != 0)
            return "Success";
        else
            return "not success";
    }

Glee

Answer 7

If you using router, try using RouteData

 string userIdQuery = string.Empty;               
 var userIdRouterValue = HttpContext.Current.Request.RequestContext.RouteData.Values["UserID"];
            if (userIdRouterValue!=null)
            {
                userIdQuery = userIdRouterValue.ToString();
            }

Ming

Answer 8

The first step is that you need to create a webservice and web method that accepts 2 parameters i.e.

[WebMethod]
public void helloworld(string name,string password
{
}

After that you simply create an object of a webservice and call the helloworld method i.e.

public Ripple.WebAdmin webService = new Ripple.WebAdmin();
webService.helloworld("username",password);

Frig