David Crowell :: Occasional Thoughts :

jQuery, AJAX, and JSON

Ray Houston :

I was playing around with Json.NET while trying to move some data back and forth between .NET and Flex

Icyflash :

自动将中文标题翻译成英文后设置为slug.利用Google Language API,JSON数据处理用的JSON.NET.

橄榄细语 :

http://json.org/ json的介绍 james.newtonking.com/.../json-net.aspx json for .net挺多人用这个的

Andrei Butnaru's blog :

AJAX callbacks with ASP .Net, jQuery, JSON and Web Services

IComeFromTheNet.net :

New Project: My Favourite Things

meestaben :

Any idea why an exception is thrown when trying to deserialize a json string like this:

JavaScriptObject obj = (JavaScriptObject)JavaScriptConvert.DeserializeObject(result);

System.TypeLoadException was unhandled

 Message="Could not load type 'System.Collections.ObjectModel.KeyedCollection`2' from assembly 'mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=969DB8053D3322AC'."

 StackTrace:

   at Newtonsoft.Json.JavaScriptConvert.DeserializeObject()

   at JSONTest.Form1..ctor()

   at JSONTest.Program.Main()

What I am doing wrong?

Thanks!

Ben

Grant :

i'm working on a very simple object being serialized in an AJAX response, however i noticed *all* of the dates being read out of my database are 1 day behind (so in the db it is stored correctly as Aug 14, 1978).  If I write the same property from the server directly to the .aspx page, or if i step thru my VS debugger, the date is correct.  Is there a reason (or a resolution) for date properties being serialized 1 day behind?  Thanks for the help!

dino :

@Grant -

"is there a reason?"  you ask.

yes, the reason is;  it is a timezone thing.  

The date is a datetime (likely) and that means it includes timezone info.  When you serialize (Aug 14 1978) out, you are getting Aug 14 1978 UCT, which is really Aug 13 1978 in your timezone.  

The resolution is to add the UCT delta before serializing.  

el_mike :

Hello all,

is there some kind of discription, manual or something, how the methods can be used? for a beginner its hard to understand with no help ;)

el_mike

NTulip :

James,

It just occured to me that when JavaScriptConvert.SerializeXmlNode function does change the json output depending on the number of "rows" being passed to the converter.

For example: an xml object containing one node is translated into:

{"totalCount": 1,

"data":

{"ConfigId":"2","URL":"viewimage.aspx?imageid=43","imgtype":"application/octet-stream","imgsize":"3 KB","imgname":"symbol.gif","ImageID":"43"}

}

while an array of rows (2 in this case) is translated into:

{"totalCount": 2,

"data":

[

{"ConfigId":"1","URL":"viewimage.aspx?imageid=12","imgtype":"application/octet-stream","imgsize":"67 bytes","imgname":"ajax_window1_trc.gif","ImageID":"12"},

{"ConfigId":"1","URL":"viewimage.aspx?imageid=13","imgtype":"application/octet-stream","imgsize":"7 KB","imgname":"client_manager.jpg","ImageID":"13"}

]

}

The difference is that the [] square brackets are included to identify an array.

Why not include those brackets all the time?

Alejandro :

This thing is absolutely beautiful..!

It enables a totally beautiful programming model, I love it! Congratulations for such a good job.

I have a question though, is there something like this for javabeans? I've heard that GWT jsonizer has some limitations...

Alejandro

Mikael :

I'm using JsonReader.Read to walk through a json string until finding a JsonToken.PropertyName whith a specific value. What I would like to do now in deserialize the json object string that follows. Something like "InnerJson"? Would that be possible?

guillaume :

Hi,

Really nice work.

One question though : Is there possible to serialize from let's say an array of custom objects and include a "totalcount" value in the JSON string ?

Thanks

Rehan :

Is there an (old?) version available perhaps that builds against the 1.1 compact framework?

Mats Andreasen :

Hi.

I always gets an exception when I try to de-serialise an object, where the class-definition contains an ArrayList member-variable. Is this a known problem?

Best regards

shabraque :

Hi,

Nice piece of software, this is exactly what I needed.

Could you please post an example how to specify which Properties / Members should be ignored by the JavaScriptConvert.SerializeObject() function.

Lets say I have a class like:

public class product

{

 public ID

 {

   get {return mID;}

   set {mID = value;}

 }  

}

How can I specify that the Property ID is to be ignored by the Serializer?

kushal :

Hello,

Congratulations and many thanks for this excellent library.

While using it I came across a situation where I wanted the SerializeObject method to only serialize "top-level" properties in a class (i.e. ignore inherited ones. I was serializing a set of Configuration properties and the ConfigurationElement class has scores of properties that I didn't want in my javascript object.)

To achieve this, I created a new Attribute called JsonTopLevelOnlyAttribute (for which the valid targets are classes only), and if this attribute is present, the Serializer adds and extra BindingFlag called DeclaredOnly when fetching the fields and properties.

I would be happy to send you the modifications for this if you like - perhaps others would find it to be useful as well.

Paulino :

For JSON array :

["\u003c"]

the value I got back after processed by JsonReader is "003c". I woud expect it should be "<" or at least I should be getting the same thing back?

For ["\t003c'], I got the same thing back, which is "\t003c" as the value.

Did I do it wrong somewhere? Please advise. Thanks

Kari :

Hi James,

Big thanks for this library!

I've run into a problem regarding the generic Dictionary<,> type. Deserialization fails for any Dictionary when the key is not a string. It appears to me that ReflectionUtils should have a corresponding GetDictionaryKeyType to the existing GetDictionaryValueType and this should be called from SetObjectMember in JsonSerializer before adding the key,value pair to the IDictionary object.

Is it likely that you might include a fix such as this in a future release?

Many thanks,

Kari

Evan :

Hey great library!

I am working on an application to interface with SmugMug's JSON API and this has worked great for Deserializing the responses. One problem I'm running into is that SmugMug will occasionally add parameters to their response, resulting in a JsonSerializationException, "Could not find member 'X' on object of type 'Y'. This is being generated in: JsonSerializer.SetObjectMember (JsonSerializer.cs line 358).

While I understand the need for throwing an error, I was wondering if there is an option for continuing on these missing members? It would be unfortunate if my application broke every time smugmug added an additional return parameter.

It seems possible to add an option similar to ReferenceLoopHandling, that would define how these events are handled. Then in SetObjectmember, if there is no member, simply returning, and handling it as though the Ignore Attribute was set. This would also remain backwards compatible with the current implementation. While I can make the change myself, I try and avoid modifying libraries so I can upgrade without a problem later on (unless I send you a patch and it gets merged in)

Thanks again for a great library!

Evan

Jake Heidt :

Fallon Massey :

It would be nice to have a conversion of the following using c# 3.0 anonymous types.

1.  JSON to var type, and

2.  var type to JSON

Once this is done, the C# code will be just like the javascript code, and not care about the fields/properties of the object.  C# then becomes a pseudo dynamic language.

Jorre Meijrink :

Christian Frank :

Hi James,

what NTulip said at sep. 24. is a serious problem depending on the application which receives the strings.

I have this problem when commiting such a string to a ExtJS JSONReader. It just won't work without the surrounding [ ].

Thanks anyway for this great library :)

Christian

David Read :

Excellent work!  Is there a way to tag a class to indicate that null property values not be serialized?  I have class that defines a protocol where a number of properties are optional.  During serialization they are included with a value of "null".  Ideally there would be a way to say that null values should be excluded from the resulting string.

Regards

Mike :

To the person who asked if there's some kind of manual for this, the best I could find was another post by the author, which should point you in the right direction.  It took me a while to find it so I thought other people might find it useful too.

james.newtonking.com/.../Json.NET-_2D00_-Simplifying-.NET-_3C002D003E00_-JavaScript-communication.aspx

Mike :

Love your library James.  One tiny request I'd make woudl be to ask for a method to wrap the very common operation of writing a name-value object.

public class JsonWriter

{

// ...

public void WriteObject(string name, object value)

{

writer.WriteStartObject();

writer.WritePropertyName(name);

writer.WriteValue(value.ToString());

writer.WriteEndObject();

}

}

I know it's a trivial method but it can dramatically reduce the amount of code you need to write.

Cheers James.

Mike :

Sorry, I misunderstood something, ignore my last post.

Michael Brown :

Is there a was to insert Json data into a dataset?

Andrew Timmins :

Juan Pena :

cc :

hello.i am chinese,thank you for you  airticle,it's very helpfull

Steve :

If you get a chance I'd love to see the introduction of deserialization towards a method signature rather than a type definition.  It's hard to write a generic JSON-RPC handler right now because there is no single well-defined type for a method call.  If we could say "here's a set of arguments with types, here's a JSON object", well, that's a generic JSON-RPC handler :)

Shiraz :

Firstly, thank you James for an excellent library! I have been trying to use the JavascriptConstructor Object but it does not seem to Serialize correctly. Not sure if this is a bug or if I am not using it correctly. See code below...

private string GetSplitButtonMenuJson()

{

   //Expected Return Value:

   //{"menu":new Ext.menu.Menu({"items":[{"text":"item 1"},{"text":"item 2"}]})}

   //Actual Return Value:

   //{"menu":{"Parameters":[{"items":[{"text":"item 1"},{"text":"item 2"}]}],"Name":"Ext.menu.Menu"}}

   System.IO.StringWriter loJSONString = new System.IO.StringWriter();

   JsonSerializer loJS = new JsonSerializer();

   JavaScriptObject loMenu = new JavaScriptObject();

   JavaScriptObject loItems = new JavaScriptObject();

   JavaScriptObject loItem1 = new JavaScriptObject();

   JavaScriptObject loItem2 = new JavaScriptObject();

   JavaScriptArray loArray = new JavaScriptArray();

   loItem1.Add("text", "item 1");

   loArray.Add(loItem1);

   loItem2.Add("text", "item 2");

   loArray.Add(loItem2);

   loItems = new JavaScriptObject();

   loItems.Add("items", loArray);

   List<Object> loParameters = new List<Object>();

   loParameters.Add(loItems);

   JavaScriptConstructor loMenuConstructor = new JavaScriptConstructor("Ext.menu.Menu",new JavaScriptParameters(loParameters));

   loMenu.Add("menu", loMenuConstructor);

   loJS.Serialize(loJSONString, loMenu);

   return loJSONString.GetStringBuilder().ToString();

}

Shiraz :

I think, the output I was expecting in my previous post may not be valid Json. Sorry for that (I am new to Json). I saw the  JavaScriptConstructor and JavaScriptParameters classes and thought they would do what I wanted. What are they intended for?

zoidbeck :

First of all thank you for this nice peace of work.

I had to implement a new DateTime parser to serialize the qooxdoo static date constructors like new Date(Date.UTC(2008,2,24,12,21,212)) but now it works like a charm.

The parser crashes when reading these static constructors throwing a SerializationEx. My fix is quite a hotfix and i did not read all of you code, but is it be possible to fix this and simply give that value-string to the jsonconverter provided for that type?

Richie Cotton :

The JsonSerializer Deserialize method throws an exception when it encounters NaN or Infinity in a numeric array.  While these values aren't officially part of the JSON spec, it would be nice if there was some way of reading them in, especially since they can be written with this library.

lvhejin :

UP

Chris :

I`m trying to parse this string:

String tmp = @"{"2018":{"Name":"School1","Location":"Location","Year":"2007"},"2266":{"Name":"School2","Location":"Location","Year":"2007"},"2291":{"Name":"School3","Location":"Location","Year":"2007"},"2293":{"Name":"School4","Location":"Location","Year":"2007"},"2610":{"Name":"School5","Location":"Location","Year":"2007"}}";

With

XmlNode s = JavaScriptConvert.DeerializeXmlNode(tmp);

But then I get an InvalidOperationException:

'JavaScriptConvert.DeerializeXmlNode(tmp)' threw an exception of type 'System.InvalidOperationException'

   base {System.SystemException}: {"This document already has a 'DocumentElement' node."}

How should I parse the multidemensional array to get the results I want?

I've also tried to put the results in a seperate class like in the example but because the identifier of the array always has a different name it also fails.

Product deserializedProduct = JavaScriptConvert.DeserializeObject<Product>(json);

dario :

Hi everybody

Is there a way to set/remove the jsonignore dynamically? What I'd like

to achieve is to limit the amount of data to be transferred to the

data strictly needed by a given request. If I set JsonIgnore that

field will always be ignored by json serializer even when it's needed;

conversely a property without jsonignore will always be serialized

even when it's not needed. I know I could implement a custom

serializer for but I was wondering if there's a different way to

accomplish this.

Thanks in advance

Ray :

Hi all,

Does json.net not recognize escape characters, e.g. \"?

Here's an example:

<code>

string img1 = "<img class=\"imgClass1\" src=\"localhost/.../check.gif\"/>"

</code>

Outputs:

<code>

"<img class=\"imgClass2\" src=\"localhost/.../createsmall.gif\"/>"

</code>

Thanks.

Ray :

I guess this forum isn't read much, but I'll ask another question anyways.

Anyone know if null values for properties in a class can be ignored when converting an ojbect of that class to JSON with JavaScriptConvert?

I'm getting the feeling that json.net can only be used on pet projects.

A serious drawback for use in web applications: json.net is not thread safe.

Ray :

Thanks JNK. I was using 1.3.1, I'll switch to 2.0 beta. How can I output javascript function names without double quotes, e.g.

{

"renderer":myRendererFunc,

"name":"myName",

"id":206

}

Thanks

Ray :

Is there a binary of the JSON.NET 2.0 beta versions compiled in .NET 2.0?

Thanks,

Ray :

Hi JNK,

For writing javascript manually (literal), do you plan on fixing this sometime soon? Perhpas by creating a JsonToken.LiteralJavaScript?

From JsonTextWriter.cs

/// <summary>

/// Writes raw JavaScript manually.

/// </summary>

/// <param name="javaScript">The raw JavaScript to write.</param>

public override void WriteRaw(string javaScript)

   {

     base.WriteRaw(javaScript);

     // hack. some 'raw' or 'other' token perhaps?

     WriteValueInternal(javaScript, JsonToken.Undefined);

   }

Thanks,

Ray :

The reason I'm asking is that JsonWriter goes into an invalid state if I call  jsonTextWriter.WriteRaw("myJSFunction") more than once and throws me an error.

Newtonsoft.Json.JsonWriterException : Token Undefined in state Start would result in an invalid JavaScript object.

Jeff liu :

matthew montgomery :

Mihai Danila :

Nick T :

Zoti :

Mister McGoo :

GREAT library man! I was getting to the point where I was facing down the daunting task of having to write my own serializer when I stumbled upon yours. It looks like you did a really good job, keep up the good work.

This isn't a big deal, but it might make for a 'nice to have' feature. Alot of JSON services I've worked with seem to omit the root element (i.e. they just return a list of objects). so rather than:

{"root": , "child":[

it starts right in with:

{"child":[

Obviously DeserializeXmlNode won't like this but some quick string manipulation will resolve the issue. You may want to consider adding an overload to allow it to insert the root node for you (just a string for the name of the root node). Again, not a big deal but handy nonetheless.

vasu :

WuJunyin :

Cool! The best lib of Json i used.

amber :

I think your work is really good.

It helps me a lot.

Thank you.

Do you have any plan of  converting it to Java version?

S&#248;ren Olesen :

YYYz :

theonlytheory :

Steve :

Fantastic work.

By the way, I can serialize and deserialize fine with your library.

But when I send a JSON string to the Silverlight (2.0) DataContractSerializer it can't deserialize the json string.

I wish Silverlight was using your library

Epsilon718 :

Epsilon718 :

Adam Kaupisch :

Adam Kaupisch :

theonlytheory :

Tony :

Json.net will support Silverlight what time?

Tony :

Hi James,

The latest source code isn't include Newtonsoft.Json.Silverlight part.

The folder is empty.

do you check it? thanks

Tony :

Hi James,

I am sorry, you are right. thanks again.

Keith :

Keith :

Sorry, I didn't know the comment had to be HTML formatted... I was going to leave it be but I noticed the code example was incorrect because a piece of it was interpreted as HTML. Reposted below with correct formatting.

When I try to deserialize JSON into an object of a class that doesn't have a default constructor (i.e. zero args) the fields in the resulting object have their default values instead of the values specified in the JSON.

For example, given a 'Customer' class that has no default constructor, the code:

var c = JavaScriptConvert.DeserializeObject<Customer>(customerJson);

results in 'c' having its fields initialized to their default values.

Is this expected behavior? Thanks.

c.barca :

Daniel M&#248;ller :

Daniel M&#195;&#184;ller :

Daniel M&#248;ller :

Figured it out, reposted:

Hi James

I noticed a few problems in Json.NET.

1) When having a custom string type that implements IConvertible it does not work.

In JsonSerializer.SerializeValue you are typecasting to a string, instead of letting the IConvertible interface do the job:

I think this should be:

At least that worked in my case.

2) Also had some problems with datetime handling. If I had a DateTime.MinValue it would try to subtract an offset when converting to UTC time, which of course resulted in an exception. In JavaScriptConvert I changed:

into:

and it worked, however I am not sure if this blows up some of the UTC handling (I only had a use for the date, not the time in my case) Just wanted to let you know about this, maybe you can look into it and find a better solution.

3) I also noticed you have changed the Date representation in BLOCKED SCRIPT

this format blew up in the javascript engine in both IE and FF on my machine.

I had to reverse back to:

Maybe this needs to be looked into aswell.

Best regards

Daniel

Andrew Lee :

Json :

Limo Grabber :

theonlytheory :

Monika :

Monika :

Benjamin :

Hello,

I have the same issue as Paulino : after Deserialize, all UTF-16 encoded characters (for example \u003c) are converted (for example to 003c, \u was removed).

How can I avoid that ?

Thank you

Benjamin :

Thank you for your answer.

I'm using Json.NET 1.3.1 because my application is running under .NET 2.0.

Doug Wood :

unruledboy :

unruledboy :

hi, could you add support for deserialize from stream?

JavaScriptConvert.DeserializeObject<T>(Stream value)

JavaScriptConvert.DeserializeObject(Stream value)

Nancy Lounsbury :

Kevin T. :

Joel N :

Brian C :

RandyB :

Karl :

There's a simple Json serializer/deserializer for the Compact Framework now available on CodePlex:

http://www.codeplex.com/JsonCF

RoyU :

I have a quenstion about date. I work with Newtonsoft.Json.dll, version 3.0.0.0

If I do the following:

string date = Newtonsoft.Json.JavaScriptConvert.SerializeObject(new DateTime(1970, 1, 1));

The value of date is "\"\\/Date(-3600000+0100)\\/\"".

I don't understand, I was expecting something like "new Date( -number- )".

Am I missing something?

RoyU :

Problem solved, sorry, it took me some time to figure it out in the documentation. Perhaps you can add this as an example to the documentation ...

I had to use the second parameter.

The following line solved the issue.

string date = Newtonsoft.Json.JavaScriptConvert.SerializeObject(new DateTime(1970, 1, 1), new JavaScriptDateTimeConverter());

Now the value is "new Date(-3600000)"

Nice!

Keep going strong, I love the library!

RoyU :

I still have one question. If I use a date and it is not a correct javascript date, it seems like I get a string "null" instead of a null (no value). Is this correct?

serdar g&#252;ner :

serdar guner :

Simon :

RoyU :

James I am sorry, I see that I din't mention that I'm working with a nullable DateTime type (DateTime? datetime). When the variable datetime = null I get a "null" string, but then I need a null-value ...

Netcougar :

Ivan :

It's good,thx!

Peter Kellner :

Tom Faust :

Scott :

Mike Hammond :

Ian :

Roberto Colombo :

Hi there James, first off thanks for the great library!

Since I can't find any example around about my problem, I'd just like to ask you if you please can tell how to create a JS array.

In my C# project I have a class "teacher" which has got only two attributes "ID" and "name". I'd like to have a JSON object like this but I don't know how to do that:

{

teachers:[

[123,"Ella Fitzgerald"],

[34,"John Brown"],

[569,"Michael John"]

]

}

Thanks in advance.

Roberto

Danny Miller :

Dennis Spaag :

Daniel Shi :

Amazing!

szmarx :