I have a string where I need to use as the body of a JSON object. I know its possible that the data could have quotes in it, so I parse through to add an escape character to those instance of quotes.. like so:
string NewComment = comment.Replace("\"", "\\\"");
However, somehow on some edgecases, a quote still makes it through. I don't know if this is something with UTF or some other issue, But I am trying to find a function that would safely create a json compatible string, I figured there has to be something like this out there, or a regex way of doing so.
Basically a TLDR is how to create a json syntax safe string from a c# string
The simple answer is don't do it this way. What if you have escaped quotes in your string? "Hello \"World\"" would become invalid with such a simple approach: "Hello \\"World\\"". JSON.Net or Newtonsoft are going to save you so many headaches in the long run.
Related
I'm getting some JSON for an outside source that can't be changed and apparently they don't understand the rules about escaping characters correctly in JSON string values. So they have a string value that might have tabs in it, for example, that should have been escaped and other invalid escape sequences like \$. I'm trying to parse this with JSON.Net but it keeps falling over on these sequences.
For example, the source might look something like this:
{
"someRegularProp": 10,
"aNormalString": "foo bar etc",
"anInvalidString": "foo <tab \$100"
}
and it's parsed with
var obj = JObject.Parse(json);
So I can fix this specific case with something like:
json = json.Replace("\t", "").Replace("\\$", "$"); // note: in this case I'm fine with just stripping the tabs out
But is there a general way to fix these problems to remove invalid escape sequences before parsing? Because I don't know what other invalid sequences they might put in there?
I don't see general way. Obviously they are using bugged library or no library at all to generate this output and unless you explore more, all you can do is try as much output from them as possible to find all problems.
Perhaps make a script to generate as much output as possible and validate all of that, then you can be at least a bit more sure.
Here is my prob, I wanted String.Format() function should take 4 objects and format string. But it throws "Input string not in a correct format error".
Here is my code,
string jsonData = string.Format("{{\"sectionTitle\":\"{0}\",\"strPushMsg\":\"{1}\",\"Language\":\"{2}\",}\",\"articleid\":\"{3}\"}}", urlsectiontitle, formatHeadline, Language, articleid);
\"{2}\",}\"
Looks like you need to escape that closing brace by doubling it:
string.Format("{{\"sectionTitle\":\"{0}\",\"strPushMsg\":\"{1}\",\"Language\":\"{2}\",}}\",\"articleid\":\"{3}\"}}", urlsectiontitle, formatHeadline, Language, articleid);
It appears you are creating JSON. This can use single quotes (which would avoid all the escaping), but even better use a tool like JSON.Net designed to create JSON. While your (partial) structure here is quite small (the unmatched } shows this is only partial), and the JSON gets bigger it is much easier to use a tool to get it right.
Deserialize JSON into C# dynamic object?
Following above question, I copy the dynamicJsonDeserilization and trying to use that in my application.
then I try to access the object as
var Data = json.deserilization(jsonstring);
Now, my string is
{"0":{"Name":"C:\\","Type":"Partition","Path":"C:\\"},"1":{"Name":"D:\\","Type":"Partition","Path":"D:\\"},"2":{"Name":"E:\\","Type":"Partition","Path":"E:\\"}}
i.e. I just have an Array on my server which I convert to JSON string and send.
As per code from best answer I should be able to access it as Data.0 but it give "End of Expression expected", Also Data[0] is giving same error. I am not sure how can I use it ? Any help is appreciated. Thanks.
Now, my string is
{"0":{"Name":"C:\","Type":"Partition","Path":"C:\"},"1":{"Name":"D:\","Type":"Partition","Path":"D:\"},"2":{"Name":"E:\","Type":"Partition","Path":"E:\"}}
Your string is indeed not valid JSON due to escaped quotes.
Those C:\ are breaking the parser. You should generate it like this, sending three backslahes:
{"0":{"Name":"C:\\\","Type":"Partition","Path":"C:\\\"} ...
I am having a few problems with trying to replace backslashes in a date string on C# .net.
So far I am using:
string.Replace(#"\","-")
but it hasnt done the replacement. Could anyone please help?
string.Replace does not modify the string itself but returns a new string, which most likely you are throwing away. Do this instead:
myString= myString.Replace(#"\","-");
On a side note, this kind of operation is usually seen in code that manually mucks around with formatted date strings. Most of the time there is a better way to do what you want (which is?) than things like this.
as all of them saying you need to take value back in the variable.
so it should be
val1= val1.Replace(#"\","-");
Or
val1= val1.Replace("\\","-");
but not only .. below one will not work
val1.Replace(#"\","-");
Use it this way.
oldstring = oldstring.Replace(#"\","-");
Look for String.Replace return type.
Its a function which returns a corrected string. If it would have simply changed old string then it would had a void return type.
You could also use:
myString = myString.Replace('\\', '-'));
but just letting you know, date slashes are usually forward ones /, and not backslashes \.
As suggested by others that String.Replace doesn't update the original string object but it returns a new string instead.
myString= myString.Replace(#"\","-");
It's worthwhile for you to understand that string is immutable in C# basically to make it thread-safe. More details about strings and why they are immutable please see links here and here
I'm using System.Web.Script.Serialization.JavaScriptSerializer() to serialize dictionary object into JSON string. I need to send this JSON string to API sitting in the cloud. However, when we serialize it, serializer replaces all the double quotes with \"
For example -
Ideal json_string = {"k":"json", "data":"yeehaw"}
Serializer messed up json_string = {\"k\":\"json\",\"data\":\"yeehaw\" }
Any idea why it is doing so? And I also used external packages like json.net but it still doesn't fix the issues.
Code -
Dictionary<string, string> json_value = new Dictionary<string, string>();
json_value.Add("k", "json");
json_value.Add("data", "yeehaw");
var jsonSerializer = new System.Web.Script.Serialization.JavaScriptSerializer();
string json_string = jsonSerializer.Serialize(json_value);
I'm going to hazard the guess that you're looking in the IDE at a breakpoint. In which case, there is no problem here. What you are seeing is perfectly valid JSON; simply the IDE is using the escaped string notation to display it to you. The contents of the string, however, are your "ideal" string. It uses the escaped version for various reasons:
so that you can correctly see and identify non-text characters like tab, carriage-return, new-line, etc
so that strings with lots of newlines can be displayed in a horizontal-based view
so that it can be clear that it is a string, i.e. "foo with \" a quote in" (the outer-quotes tell you it is a string; if the inner quote wasn't escaped it would be confusing)
so that you can copy/paste the value into the editor or immediate-window (etc) without having to add escaping yourself
Make sure you're not double serializating the object. It happened to me some days ago.
What you're seeing is a escape character
Your JSON is a String and when you want to have " in a string you must use one of the following:
string alias = #"My alias is ""Tx3""";
or
string alias = "My alias is \"Tx3\"";
Update
Just to clarify. What I wanted say here is that your JSON is perfectly valid. You're seeing the special characters in the IDE and that is perfectly normal like Jon & Marc are pointing in their answers and comments. Problem lies somewhere else than those \ characters.