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C# String.Format replaces escaped quotes into "

I'm trying to format a String using the String.Format function, but my double quotes keep getting replaced by the HTML safe version of this (").
Needless to say this is not the result I would expect.
My current code looks like this
string String= String.Format("{0}: {{ name: \"{1}\"}}", node.Category, node.Name);
// Output ==> SomeCategory: { name: "SomeName" }
I've tried replacing the " by actual quotes in the output, but that also didn't work.Is there some voodoo I can use to fix this?
Thanks in advance!

This is not caused by String.Format(), more likely it is caused by whatever you use to view the data, or by something that happens before you view the data.
Judging from your format string it looks like you're trying to create a JSON string to return (possibly from a service). There is a big chance something will HTML encode your string on it's way to the client. The problem lays there, not in your string formatting, and thus trying to fix it there will not work.

Try to use HTML decode and encode
That way you can turn them in actual quotes.
HttpUtility.HtmlDecode
Source: http://msdn.microsoft.com/en-us/library/aa332854%28v=vs.71%29.aspx
Stackoverflow source: " instead sign of quote (")

How do I parse a query string with "&" in the value using C#?

I have a C# custom webpart on a sharepoint 2007 page. When clicking on a link in an SSRS report on another page, it sends the user to my custom webpart page with a query string like the following:
?tax4Elem=Docks%20&%20Chargers&ss=EU%20MOVEX&Phase=1&tax3Elem=Play%20IT&tax5Elem=Charger
Take note of the value for "tax4Elem", which is basically "Docks & Chargers". (The ampersand can actually come up in "tax4Elem", "tax3Elem", and "tax5Elem").
I cannot have the ampersand in that value encoded so I will have to work with this.
How do I parse this query string so that it doesn't recognize the "&" in "Docks & Chargers" as the beginning of a key/value pair?
Thanks in Advance!
kate

If you really cannot correct the URL, you can still try to parse it, but you have to make some decisions. For example:
Keys can only contain alphanumeric characters.
There are no empty values, or at least, there is always an equal sign = after the key
Values may contain additional ampersands and question marks.
Values may contain additional equal signs, as long as they don't appear to be part of a new key/value pair (they are not preceded with &\w+)
One possible way to capture these pairs is:
MatchCollection matches = Regex.Matches(s, #"\G[?&](?<Key>\w+)=(?<Value>.*?(?=$|&\w+=))");
var values = matches.Cast<Match>()
.ToDictionary(m => m.Groups["Key"].Value,
m => HttpUtility.UrlDecode(m.Groups["Value"].Value),
StringComparer.OrdinalIgnoreCase);
You can then get the values:
string tax4 = values["tax4Elem"];
Note that if the query string is "invalid" according to our rule, the pattern may not capture all values.

I think you can't parse that string correctly - it has been incorrectly encoded. The ampersand in "Docks & Chargers" should have been encoded as %26 instead of &:
?tax4Elem=Docks%20%26%20Chargers&ss=EU%20MOVEX&Phase=1&tax3Elem=Play%20IT&tax5Elem=Charger
Is it possible to change the code that generated the URL?

Obviously the request is incorrect. However, to work-around it, you can take the original URL, then find the IndexOf of &ss=. Then, find the = sign immediately before that. Decode (with UrlDecode) then reencode (with UrlEncode) the part between the = and &ss= (the value of tax4Elem). Then, reconstruct the query string like this:
correctQueryString = "?tax4Elem=" + reencodedTaxValue + remainderOfQueryString
and decode it normally (e.g. with ParseQueryString) into a NameValueCollection.

Or you can use HttpServerUtility.HtmlDecode method to decode the value to '&' (ampersand) sign

Plus sign in query string

I have a webapp created using C# and asp.net. I placed a parameter value in the querystring with a plus(+) sign. But the plus sign disappear.
How can I include the plus sign(+) in the query string without disappearing?
Please advise.
Thanks.
Edit: added code with UrlEncode
string str = Server.UrlEncode(Requery.QueryString["new"]);

+ sign has a semantic meaning in the query string. It is used to represent a space. Another character that has semantic importance in the query string is & which is used to separate the various var=value pairs in the query string.
Most server side scripts would decode the query parameters before using them, so that a + gets properly converted to a space. Now, if you want a literal + to be present in the query string, you need to specify %2B instead.
+ sign in the query string is URL-decoded to a space. %2B in the query string is URL-decoded to a + sign.
See the difference between
http://www.google.com/search?q=foo+bar
and
http://www.google.com/search?q=foo%2Bbar
In the above examples, Google's server script is URL-decoding the query parameters and then using them to do the search.
URL-encoding is nothing but % sign followed by the hex-code of the special character. For example, we know that the hex code of A is 0x41 (decimal: 65). Try this:
http://www.google.com/search?q=%41
Hope this makes URL-encoding clear.
So, if you want the + sign to be preserved when a JavaScript is fetching a URL with + signs in its query parameters and a server side script would process the query parameters after URL-decoding it, you should URL-encode the query parameters in the URL before using issuing the HTTP get request so that all + signs are converted to %2B's when the request reaches the server side script. Now when the server side script URL-decodes the query string, all %2B's gets converted back to + signs which is what you want.
See Encode URL in JavaScript? to learn how to URL-encode the parameters using JavaScript. Short answer from the discussion there:
var encodedURL = "http://example.com/foo.php?var=" + encodeURIComponent(param);

You should URLEncode your query string values to make sure any special characters are not lost.

Look at HTML URL Encoding Reference
You need to Encode the + sign - It's value should be %2B

I alter my previous statement so no one gets confused!
Create your url using the Server.UrlEncode.
e.g.
string myUrl = "http://myurl?param1=" + Server.UrlEncode("my+param+1");

For the solution, I have applied:
Step 1:Use Server.UrlEncode method for encoding the URL parameter.
Response.Redirect("YourURL?parameter=Server.UrlEncode(parameterValue.ToString().Trim()");
step 2: on another side, you get a string with a plus(+) sign.
var parameter = Request.QueryString["parameterValue"].ToString().Trim();
This is the result: %2beH8 --> +eH8

Other simple way is, Request.Url.ToString().Substring(Request.Url.ToString().IndexOf("=") + 1) assuming that my URL is, http://localhost/MyApp/Activate.aspx?ActivationCode=cHbtqH9P2dDZkx/mYUgFFo7nrNqSFgqdPisAzzu5/nwlEYDOHI+CQw==

before send you parameter, you need check if the parameter contains plus sign, if have you need replace to one flag, for example:
the parameter is: klasjdlkasd+djid3223
can you replace: klasjdlkasdFLAGdjid3223
and when you go convert, you need replace angain
klasjdlkasd+djid3223

Try this, it works for me:
Request.QueryString["new"].Trim();

The solution is to ALWAYS include .Replace(" ", "+") when you request querystring
string s = Request.QueryString["id"].Trim().Replace(" ", "+");
source: http://www.webmasterworld.com/forum47/3238.htm

Add this line in Decrypt Funcation:
strText = strText.Replace(" ", "+");

Adding an unescaped query parameter in C#

I am trying to add an unescaped parameter to a URL with the help of UriBuilder. How can I prevent the characters of the parameter to be escaped?
query.Set("oauth_signature", CONSUMER_SECRET + "%26");
builder.Query = query.ToString();
The resulting URL always contains % as an escaped sequence as the oauth_signature value (which is %25 apparently).

%26 is & right? Why not just do
query.Set("oaut_signature", CONSUMER_SECRET + "&");

A dirty workaround would be to use a token to identify where the parameter should go in, and string.Replace it afterwards. It's not safe though, which is probably why there's no easy way with UriBuilder.

Url encoding quotes and spaces

I have some query text that is being encoded with JavaScript, but I've encountered a use case where I might have to encode the same text on the server side, and the encoding that's happening is not the same. I need it to be the same. Here's an example.
I enter "I like food" into the search box and hit the search button. JavaScript encodes this as %22I%20like%20food%22
Let's say I get the same value as a string on a request object on the server side. It will look like this: "\"I like food\""
When I use HttpUtility.UrlEncode(value), the result is "%22I+like+food%22". If I use HttpUtility.UrlPathEncode(value), the result is "\"I%20like%20food\""
So UrlEncode is encoding my quotes but is using the + character for spaces. UrlPathEncode is encoding my spaces but is not encoding my escaped quotes.
I really need it to do both, otherwise the Search code completely borks on me (and I have no control over the search code).
Tips?

UrlPathEncode doesn't escape " because they don't need to be escaped in path components.
Uri.EscapeDataString should do what you want.

There are a few options available to you, the fastest might be to use UrlEncode then do a string.replace to swap the + characters with %20.
Something like
HttpUtility.UrlEncode(input).Replace("+", "%20");

WebUtility.UrlEncode(str)
Will encode all characters that need encoded using the %XX format, including space.