Jint - Javascript Interpreter for .NET

New Post: Wrong implementation of array.CopyTo in jsDateConstructor?

sebandres — Thu, 23 Feb 2012 00:36:35 GMT

Hello!

First of all great project!! It really works really well for what I am in need of.

I am using version 0.9.2 and today I found what seems to be a bug on the code in several of the SetXXX functions of the jsDateConstructor.cs file.

On this functions the basic idea as I would guess it is that you use the first parameter and then pass the rest to the more specific functions, let's say I want to set hour, minute and second, the SetHour function is called first, uses the parameter [0] and then passes the rest to the SetMinute function that uses the parameter[0] and so forth.

this is implemented like this:

            if (parameters.Length > 1) {
                JsInstance[] innerParams = new JsInstance[parameters.Length - 1];
                parameters.CopyTo(innerParams, 1);
                target = (JsDate)SetSecondsImpl(target, innerParams);
            }

Here parameters is the original array and innerParms is the array we want to send to the next function.

The problem is at parameters.CopyTo(...) , this call actually tries to copy the entire parameters into innerParams starting at position 1 (of the innerParams array), this is a problem because we just created this array with 1 less item that the original parameters array. You can see the full description of this function here: http://msdn.microsoft.com/en-us/library/06x742cw.aspx

What I think is correct is to replace the previous line with the Array.Copy function like this:

Array.Copy(parameters, 1, innerParams, 0, parameters.Length - 1);

this will copy all elements from parameters starting at position 1 into innerParams starting at position 0. Here you can see an explanation of the Array.Copy function: http://msdn.microsoft.com/en-us/library/z50k9bft.aspx

Please ignore this if I'm totally off the mark here.

Keep up the good work!

Regards,

Sebastian Andres

Created Issue: undefined + Array Mistake [6944]

fijode — Sat, 18 Feb 2012 20:45:38 GMT

undefined+[343]
gives
NaN
but should give
"undefined343"

Commented Issue: NaN + Array mistake [6943]

fijode — Sat, 18 Feb 2012 20:41:02 GMT

NaN+[234]
gives
NaN
but should give
"NaN234"
Comments: oops, I ment NaN+["test"]

Commented Issue: NaN + Array mistake [6943]

fijode — Sat, 18 Feb 2012 20:39:49 GMT

NaN+[234]
gives
NaN
but should give
"NaN234"
Comments: the same mistake exist for NaN+[234]

Created Issue: NaN + Array mistake [6943]

fijode — Sat, 18 Feb 2012 20:37:55 GMT

NaN+[234]
gives
NaN
but should give
"NaN234"

Commented Issue: Addition Mistake [6942]

fijode — Sat, 18 Feb 2012 20:33:51 GMT

true+["8798"]
should give
"true8798"
but gives
2
Comments: the same problem with true+["test"] should return "truetest" but was 2

Created Issue: Addition Mistake [6942]

fijode — Sat, 18 Feb 2012 20:32:15 GMT

true+["8798"]
should give
"true8798"
but gives
2

Created Issue: NaN.ToString() with wrong casing [6941]

fijode — Sat, 18 Feb 2012 16:43:23 GMT

I noted, that

return NaN+""
will return "nan" but should be "NaN"

I hope your'll fix this mistake, soon...

New Post: InvalidProgramException on Windows Phone on Emitted function call

shaharprish — Thu, 16 Feb 2012 23:49:46 GMT

Hi,

I am using a ported version of JINT on Windows Phone.

Apparently, WP7.1 supports Emit, and so the code seems to be running. However, I am getting an InvalidProgramException when trying to call a method on an object I SetParameter'ed.

The method gets wrapped here:

ProxyHelper.cs: public JsMethodImpl WrapMethod(MethodInfo info, bool passGlobal) {

And the exception (InvalidProgramException) gets raised here:

NativeMethod.cs: public override JsInstance Execute(Jint.Expressions.IJintVisitor visitor, JsDictionaryObject that, JsInstance[] parameters)

I am assuming that the emitted code is incompatible with SilverLight, but not sure why.. So wondering if someone can point me at where to start debugging it.

Thanks

New Post: Setting permissions per namespace

SeriousSamP — Mon, 13 Feb 2012 18:27:22 GMT

Hi,

Firstly, thanks for this awesome project!

Please forgive me if I say something stupid here; I am yet to go through any official computing training and am just self-taught at this stage. It seems to me like being able to set access permissions per namespace would be a really neat and simple way of setting up an API for an application using Jint. I have a project that I have been working on for some time that requires scripted extensions to be shared between users and I had previously been using the MSScriptControl to achieve this but it was proving to be too limiting.

I am now trying to convert the project to using Jint. I need to provide access to a quite complex namespace with 60+ classes at the moment and I would like to not provide access to the rest of the CLR. Is there any way I can do this without having to rewrite all of my existing classes?

ThomasMaierhofer achieved something similar to this here: http://jint.codeplex.com/discussions/211291

So, in summary: Is this possible? And if it is, why is this not a feature of Jint?

Thanks for your help,

Sam.

New Post: What's up with string methods?

krisoye — Sat, 11 Feb 2012 23:15:11 GMT

I also noticed that JsString does not implement IComparable. The script attempting to execute does not pass a comparer so it falls through to the default List<JsInstance>.Sort() which fails due to the unimplemented interface. Am I wrong to expect that?

            if (compare != null) {
                try {
                    values.Sort(new JsComparer(Global.Visitor, compare));
                }
                catch (Exception e) {
                    if (e.InnerException is JsException) {
                        throw e.InnerException;
                    }

                    throw;
                }
            }
            else {
                values.Sort();
            }

New Post: Scripting Shorthand Question

krisoye — Fri, 10 Feb 2012 01:25:59 GMT

Is it possible to easily implement (e.g. without creating my own wrapper, overriding TryGetProperty, etc) Firefox-like shorthand notation:

Example:

document.foo.bar.value = 'Frank';

New Post: Cancel/stop a run

jorgeleo — Tue, 07 Feb 2012 19:02:50 GMT

Wating for the approval:

http://jint.codeplex.com/SourceControl/network/Forks/jorgeleo/StopExecution/contribution/1841

New Post: Jint Used In FocusOPEN DAM System

daydream — Mon, 06 Feb 2012 14:24:04 GMT

Hi,

I'm not sure if it is appropriate to post in this forum on this subject, if not, please accept my apologies in advance. This is just an fyi to let you know that we have included Jint in FocusOPEN, our open source .NET Digital Asset Management system to provide scripting support and also to enable a REST API that users can extend themselves with server-side JavaScript. There is more info on FocusOPEN site here: http://www.digitalassetmanager.com

Jint been included for several releases now and so far we have been more than pleased with the elegance, stability and flexibility of the module. We fully intend to develop further features for end users using Jint, including a hooks system that will allow end users to customise our product without modifying the core code. All that has been made possible by Jint and it has considerably expanded the scope of what we can offer to our users, especially those who might not be expert with .NET.

Keep up the good work guys!

Ralph Windsor

Daydream, developers of FocusOPEN Digital Asset Manager

New Comment on "Exposing Javascript functions to the CLR"

artyprog — Mon, 06 Feb 2012 08:47:36 GMT

Idem: list = list.ConvertAll<System.Double>( function (x) { return x * x; });

New Comment on "Exposing Javascript functions to the CLR"

artyprog — Mon, 06 Feb 2012 08:46:37 GMT

A little typo :-) var list = new System.Collections.Generic.List<System.Int32>(); Regards

Created Issue: Cannot call methods in nested classes [6940]

Arktronic — Sun, 05 Feb 2012 23:14:50 GMT

Methods of nested classes cannot be executed. This appears to be due to .NET's naming scheme of "Assembly.Class+NestedClass", specifically the plus sign. Using something like "$" in place of "+" for bidirectional name translation would work well, I believe, since JS is fine with dollar signs in names while .NET isn't. A quick and dirty change in NativeConstructor.cs line 50 to:

Name = type.FullName.Replace('+', '$');

allows methods residing in nested classes to be called, although obviously this isn't a good fix by any means.

New Post: Noob question: how to use C# objects from JavaScript?

Uhehesh — Sat, 04 Feb 2012 09:27:51 GMT

Thank you. This works.

And how to add methods? It seems that I have to declare them and make wrappers (?). How to do that? (Maybe I am real noob if I even can't understand how to...)

For example I have send method, but it throws exception when trying to call it. I should redirect these calls to packet class. How?

New Post: Noob question: how to use C# objects from JavaScript?

krisoye — Fri, 03 Feb 2012 22:44:09 GMT

I am not an expert on Jint (yet). I wish I was. I am having a few issues of my own.

I'd look at other classes in Jint's native namespace. JsRegExpConstructor is a constructor that supports multiple arguments:

It overrides Execute instead of Construct and calls a constructor method depending on the number of args. Perhaps you can do something similar?

In JsPacketConstructor class:

       public override JsInstance Execute(IJintVisitor visitor, JsDictionaryObject that, JsInstance[] parameters) {
            if (parameters.Length == 0) {
                return visitor.Return(New());
            }
            return visitor.Return(New(Convert.ToInt16(parameters[0].ToString()), Convert.ToBoolean(parameters[1].ToString())));
        }

...

public JsObject New() { return New(0, false); }

public JsObject New(short p, bool f) { Global.WrapClr(new packet(p, f)); }

Anyway... not sure this works but I would look at the other constructor types in Jint's Native namespace if not.

New Post: Cancel/stop a run

igorh — Fri, 03 Feb 2012 07:41:13 GMT

Thanks, jorgeleo.

My apologies, the code was OK. I have been confused by the VS exception assistant, which reproducibly reported 'Exception has not been caught', but actually, if you ignore the message and proceed, the exception is processed correctly. This is of course just a debugging issue. In release, everything works fine.

I still do not understand why the VS exception assistant is not reacting properly in this situation (even if you disable it, you would still get a VS exception message) , but maybe this is intended behavior.

Anyway, the suggestion with the AbortExecution property seems to be a proper solution to the issue.