I have an ANTLR grammar that defines a DSL (domain specific language). This grammar is relatively simple. It is parsing the language and outputting C code to create a very basic translator.
This language is meant to be used in C# application (typed into some sort of control, whether it be RichTextBox or a custom control) and one requirement is to have syntax highlighting for this language. I have scoured the Internet in hopes of finding some sort of information on how to accomplish this, or find a tool to make this a little easier on myself.
After not finding too much information, my best assumption would be that I need to use the ANTLR generated lexer to look at the tokens and color them accordingly. Is this the correct path of action, or is there some other method/tool to provide syntax highlighting for custom domain specific languages? If this is the correct method, how do I go about recognizing specific tokens?
If I left out any important information, please ask! Thanks!
I successfully used AvalonEdit for a similar project of mine. I just created a small editor with the correct syntax highlighting.
It is very easy and quick to get it up and running in your project. You just have to provide it with a simple XML file to document the syntax of your DSL and you will have a colored output out-of-the-box as a WPF control.
It looks like they added completion facilities since I used it, I don't have experience on that part though, but I suspect it is also very well done if the quality is the same as the colouring.
This language is meant to be used in C# application (typed into some sort of control, whether it be RichTextBox or a custom control) and one requirement is to have syntax highlighting for this language.
Consider using Scintilla for your control. It's a text control for IDE-style text editing. Notepad++ uses it for its text control, as does the SciTE IDE from which it originates. I've used it in a small, custom IDE project written in C# using an unofficial .NET-specific version -- I think it was ScintillaNET.
Scintilla supports custom keyword highlighting and also a variety of programmable features like squiggly-line underlining and things like that.
If you have a control that you'd rather use, I think it's reasonable to use a small ANTLR lexer to produce tokens for you. Each token contains the line number, starting character position, source text, and token type -- everything you'd need to know what to highlight and how. The only hassle would be running the text through the lexer each time the text is changed. There are efficient ways to do that without re-lexing the entire document, but it's still something to keep in mind.
Related
Im writing a simple code editor just like visual studio code editor.
btw i have a textbox and wanna know how can i underline syntactical errors?
i`v searched the web, but did not find something usefull. any one got any refernce of documentation for C# compiler to help me in this topic?
thanks all and sorry for my bad english..
If you're doing this for a real-world scenario, there are good commercial options available. You need to look at using the CodeDom classes which can take your input text and convert it into an object model which can then be compiled into an assembly.
If there are compiler errors, they will be returned as a collection of CompilerError objects. These will tell you the line number, character number, and error message, so you can display the error.
There are significant drawbacks to using CodeDom, however. It is older technology and has not been updated to keep pace with the language changes so there are limitations in what it can parse. If you want to write your own parser, you need to look at language tools like lexx and yacc or Roslyn.
With a simple textbox control you certainly cannot do that. At least you need to use a RichTextBox control (comes in a variety of flavors, for WPF, WinForms, from Office...), to do some code formatting. As a first exercise, I would suggest you try to color keywords in your editor. That's a fairly easy task (and error recovery is not a problem) and may show you how to use the control.
I'm using C# and Visual Studio 2012 to implement syntax highlighting of a language embedded in html (much like ASP code inside <% %>). So far, I've found out that I need to use IProjectionBuffer to achieve this, but there are no examples of how to do this using MEF, apart from a somewhat vague description here: http://msdn.microsoft.com/en-us/library/dd885240.aspx#projection. I tried to assign spans of text from the ITextBuffer that is "imported" through MEF to an IProjectionBuffer, but it had no effect.
Does anybody have any ideas as to how to proceed?
There is a built in feature for this purpose I think. I used to deal with text highlighting in C# code with MEF with tags. I think you shold start with Text.Classification.
There is a lack of documentation sadly, but I think you should build a lexer or somthing similar for the lingual part MSDN:DLR (features) may can help you,
The DLR allows language implementers to avoid creating lexical
analyzers, parsers, semantic analyzers, code generators, and other
tools that they traditionally had to create themselves.
detect the delimiters, and color it through classification.
Here is an example project to customize C# code displaying.
Presently I'm trying to build up a text editor for the PHP language which should have the feature of code completion, i.e. if i start to type a word a dynamically created drop down list will display all available keywords starts with my typed letters. Can any body suggest me how it can be done. Idea will be enough for me. If possible please provide me a link to such simple application build in C#.
Considering that in general it's not an easy task, so there is no some "easy" application.
Even if in general idea is not a rocket science. You need to define a dictionary of words, corresponding to some key. When you type "." (in C#) you have to pick from the dictionary all words corresponding to the key equal to the word found on left side from the "."
To do it real working applicaiton is not so easy. By the way I can recommend to have a look on MonoDevlop look on their editor.
I worked with it years ago to make a simple editor for DSL company needed, and spend not small amount of time to correctly understand intenals, integrate well "my new language", "detach" control from Mono and inject into our applicaitons, like a dockable window.
If I where you I would really try to avoid the wheel... code completion is something that most IDE's now come with so what you are after is already available...
That being said, what I would try would be to go over the PHP API and construct a Suffix tree. This type of tree usually allow for a fast way to look for a given word. Once you index the API, you would also add in any other variable the user adds while he/she is performing the actual programming.
You could kick the search automatically in your suffix tree after the user has entered the 3rd letter, or maybe provide means for the user to activate it manually, like the Ctrl-Space keyboard most IDE's (Visual Studio, Netbeans, Eclipse, etc) have.
Note that this could get tricky, since you might want to select the appropriate variable type.
MS Word has this capability in its Hebrew and Arabic versions. I would like to achieve this in a windows desktop application, using .Net (may be with win-api calls).
As explained in the link provided by Otaku here, current rich text edit controls can not handle this (unless you go for the hack OP in that Q did, which did not seem like a very good solution).
You could write code to do this manually yourself, ditching the text edit control completely, but that would probably mean a lot of work. It took Microsoft years to get support for combining diacritics working properly in MSWord. I would search for open source software that has this capability, and look at how other developers have done it. It might be hard to find, though, and you would likely have to step outside .NET-land. Maybe OpenOffice can do this?
This discussion might also be of help.
I am afraid that you will find, though, that you'll have to manually parse the Unicode and assign colors to the correct glyphs. If you want to be complete, that is one heck of a job.
How do I syntax highlight in a richtextbox control AS THE USER TYPES and USING A String[] keywords. I will be publishing a lightweight notepad to the web soon and I want it to have syntax highlighting. I am using Windows forms. Can someone post a code example?
RichTextBox syntax highlighting (talks about RichTextBox itself - minimal features but exactly what you asked for here)
A textbox/richtextbox that has syntax highlighting? [C#] (talks mostly about other ways of doing it)
The Scintilla control is an excellent source code editor that includes syntax highlighting amongst a whole range of other features. You can embed it in your own app and there is a .NET wrapper available.
With Scintilla you can specify the keywords and it will then apply the syntax highlighting as you type.
Are you using WinForms or WPF?
If WPF, you could have a look at AvalonEdit. It's free and open source, and it's used in SharpDevelop (open source IDE).
You can change the font of selected words in the richtextbox. Take a look at the Select and SelectedFont properties of the control.
But essentially, you need to iterate through the words, check if a word is present in your keywords, and then change the font, using the above-mentioned properties.
Not exactly an answer to your question, but have you looked at the text editor component from SharpDevelop? It's quite lightweight (<200kB IIRC), can be easily embedded in WinForms applications and has syntax highlighting for several languages built in.
Otherwise, you might want to look at this CodeProject page. It reformats the RTF while you type, which is not very efficient for large files, and it contains a few creepy catch (Exception) { } blocks, so I'm not sure if I would use it in a life-critical application, but it's definitely a good starting point to see how it can be done.
Syntax highlighting is not an easy task to perform efficiently. Many solutions you can find (like the ones involving modification of RTF) are a one time solution. If you want to highlight and un-highlight words on the fly during edition, your code has to be ready for it. I would not reinvent the wheel and use ICSharp.TextEditor or alike to solve your problem.