How can I remove item from querystring in asp.net using c#?
C#.Netasp.netQuery StringC# Problem Overview
I want remove "Language" querystring from my url. How can I do this? (using Asp.net 3.5 , c#)
Default.aspx?Agent=10&Language=2
I want to remove "Language=2", but language would be the first,middle or last. So I will have this
Default.aspx?Agent=20
C# Solutions
Solution 1 - C#
If it's the HttpRequest.QueryString then you can copy the collection into a writable collection and have your way with it.
NameValueCollection filtered = new NameValueCollection(request.QueryString);
filtered.Remove("Language");
Solution 2 - C#
Here is a simple way. Reflector is not needed.
public static string GetQueryStringWithOutParameter(string parameter)
{
var nameValueCollection = System.Web.HttpUtility.ParseQueryString(HttpContext.Current.Request.QueryString.ToString());
nameValueCollection.Remove(parameter);
string url = HttpContext.Current.Request.Path + "?" + nameValueCollection;
return url;
}
Here QueryString.ToString()
is required because Request.QueryString
collection is read only.
Solution 3 - C#
Finally,
hmemcpy answer was totally for me and thanks to other friends who answered.
I grab the HttpValueCollection using Reflector and wrote the following code
var hebe = new HttpValueCollection();
hebe.Add(HttpUtility.ParseQueryString(Request.Url.Query));
if (!string.IsNullOrEmpty(hebe["Language"]))
hebe.Remove("Language");
Response.Redirect(Request.Url.AbsolutePath + "?" + hebe );
Solution 4 - C#
My personal preference here is rewriting the query or working with a namevaluecollection at a lower point, but there are times where the business logic makes neither of those very helpful and sometimes reflection really is what you need. In those circumstances you can just turn off the readonly flag for a moment like so:
// reflect to readonly property
PropertyInfo isreadonly = typeof(System.Collections.Specialized.NameValueCollection).GetProperty("IsReadOnly", BindingFlags.Instance | BindingFlags.NonPublic);
// make collection editable
isreadonly.SetValue(this.Request.QueryString, false, null);
// remove
this.Request.QueryString.Remove("foo");
// modify
this.Request.QueryString.Set("bar", "123");
// make collection readonly again
isreadonly.SetValue(this.Request.QueryString, true, null);
Solution 5 - C#
I answered a similar question a while ago. Basically, the best way would be to use the class HttpValueCollection
, which the QueryString
property actually is, unfortunately it is internal in the .NET framework.
You could use Reflector to grab it (and place it into your Utils class). This way you could manipulate the query string like a NameValueCollection, but with all the url encoding/decoding issues taken care for you.
HttpValueCollection
extends NameValueCollection
, and has a constructor that takes an encoded query string (ampersands and question marks included), and it overrides a ToString()
method to later rebuild the query string from the underlying collection.
Solution 6 - C#
Try this ...
PropertyInfo isreadonly =typeof(System.Collections.Specialized.NameValueCollection).GetProperty("IsReadOnly", BindingFlags.Instance | BindingFlags.NonPublic);
isreadonly.SetValue(this.Request.QueryString, false, null);
this.Request.QueryString.Remove("foo");
Solution 7 - C#
- Gather your query string by using
HttpContext.Request.QueryString
. It defaults as aNameValueCollection
type. - Cast it as a string and use
System.Web.HttpUtility.ParseQueryString()
to parse the query string (which returns aNameValueCollection
again). - You can then use the
Remove()
function to remove the specific parameter (using the key to reference that parameter to remove). - Use case the query parameters back to a string and use
string.Join()
to format the query string as something readable by your URL as valid query parameters.
See below for a working example, where param_to_remove
is the parameter you want to remove.
Let's say your query parameters are param1=1¶m_to_remove=stuff¶m2=2
. Run the following lines:
var queryParams = System.Web.HttpUtility.ParseQueryString(HttpContext.Request.QueryString.ToString());
queryParams.Remove("param_to_remove");
string queryString = string.Join("&", queryParams.Cast<string>().Select(e => e + "=" + queryParams[e]));
Now your query string should be param1=1¶m2=2
.
Solution 8 - C#
You don't make it clear whether you're trying to modify the Querystring in place in the Request object. Since that property is read-only, I guess we'll assume you just want to mess with the string.
... In which case, it's borderline trivial.
- grab the querystring off the Request
- .split() it on '&'
- put it back together into a new string, while sniffing for and tossing out anything starting with "language"
Solution 9 - C#
Get the querystring collection, parse it into a (name=value pair
) string, excluding the one you want to REMOVE, and name it newQueryString
Then call Response.Redirect(known_path?newqueryString)
;
Solution 10 - C#
You're probably going to want use a Regular Expression to find the parameter you want to remove from the querystring, then remove it and redirect the browser to the same file with your new querystring.
Solution 11 - C#
Yes, there are no classes built into .NET to edit query strings. You'll have to either use Regex or some other method of altering the string itself.
Solution 12 - C#
If you have already the Query String as a string, you can also use simple string manipulation:
int pos = queryString.ToLower().IndexOf("parameter=");
if (pos >= 0)
{
int pos_end = queryString.IndexOf("&", pos);
if (pos_end >= 0) // there are additional parameters after this one
queryString = queryString.Substring(0, pos) + queryString.Substring(pos_end + 1);
else
if (pos == 0) // this one is the only parameter
queryString = "";
else // this one is the last parameter
queryString=queryString.Substring(0, pos - 1);
}
Solution 13 - C#
well I have a simple solution , but there is a little javascript involve.
assuming the Query String is "ok=1"
string url = Request.Url.AbsoluteUri.Replace("&ok=1", "");
url = Request.Url.AbsoluteUri.Replace("?ok=1", "");
Response.Write("<script>window.location = '"+url+"';</script>");
Solution 14 - C#
string queryString = "Default.aspx?Agent=10&Language=2"; //Request.QueryString.ToString();
string parameterToRemove="Language"; //parameter which we want to remove
string regex=string.Format("(&{0}=[^&\s]+|{0}=[^&\s]+&?)",parameterToRemove);
string finalQS = Regex.Replace(queryString, regex, "");
Solution 15 - C#
Parse Querystring into a NameValueCollection. Remove an item. And use the toString to convert it back to a querystring.
using System.Collections.Specialized;
NameValueCollection filteredQueryString = System.Web.HttpUtility.ParseQueryString(Request.QueryString.ToString());
filteredQueryString.Remove("appKey");
var queryString = '?'+ filteredQueryString.ToString();