The following procedures illustrate how to create and compile a codedom graph that generates a class containing two fields, three properties, a method, a constructor, and an entry point. I have a number of websites web forms rather than web application projects written in vb which are all built for asp. It is certainly a very useful skill when it comes to developing addins or other software that requires language independant code. For example, the t4 uses the codedom under the covers to generate. An entity class enables you to create objects and collections which can interact with other objects and collections. The article provides an insight on how to create assemblies dynamically. How to implement inotifypropertychanged with codedom in a little series of posts i showed how to create runtime class that extend a base entity to implement inotifypropertychanged. Although i say that the codedom has a tree structure, there is one complication to be aware of. The codedom namespace contains classes that abstract the idea of code. In this example, the generating class is named sample, and the. For instance, have the user click a button to load the text file and upon load, generate the required. Net language from that single abstract codedom representation. In lib c example, since lib c v1 is lower that lib c v2, we will get same exception when that lib is attempted to load while executing code in lib b lib b requires lib c.
Net api which allows you to programatically compile code using the. For each example, ask yourself which kind of metaprogramming youre observing. Net, represent more than an evolution in development skills and methodologies for microsoft developers it represents a revolution in how software is designed, written and deployed. A good starting point for codedom will be to start. I spent sometime to understand codedom and in the process wrote a sample which will help me understand this technology better. Two important usage of codedom are 1 templated code generation and 2 dynamic code compilation. There exist no complete parsers for codedom that i know of, which is also mentioned on the bcl team blog. Adds the necessary authorizedtype elements in the web. The following are the list of classes, which would be used to create the assembly. Using the codedom namespace requires you to think like the compiler and parse. Entity classes are the pillars for building a solid business layer of the application. Net core web api app how to export data in excel, pdf, csv, word, json, xml.
Several tutorials on using the codedom document exist, with most of them focusing on creating a source code file. Some of the more indepth examples demonstrate both kinds simultaneously. Net tool to allow assemblies to be disassembled back into the high level language that produced them. Also inherent in the classic definition of metaprogramming is the notion that the. Codetypedeclaration class1 gcnew codetypedeclarationclass1. Net compilers and programatically construct code without just pasting together strings.
That is what i am going to explain in this article, to compile code using codedomprovider. Codedom is the technology that provides this capability, and through the use of languagespecific code providers, you can convert an abstract codedom graph into a source code file in any language that has a provider available. You can also download a zip file containing all of the above source code. Does microsoft have documentation on how to use vbcodeprovider and codedom or any. Remarks codetypereference can be used to represent a data type to many types of codedom objects many objects or properties throughout the system. The codedom provides types that represent many common types of source code elements.
Even when we made the config change, the stalled workflows did not recover. Heres an example of using the preprocessor on the file test. I wanted to share the sample i wrote with everyone so. The parameters are easily solved with existing gui components. The following example demonstrates this using a constructor overload to set the name property. Codedom namespace use this type of object to store data types. Codedom is language independent code representation, which is defin. This object graph can be rendered as source code using a codedom code generator for a supported programming language. After defining code in this abstract manner, you can use a languagespecific codeprovider class to generate code in any. Net codedom by examining the inputs and outputs of a working source. I have seen many articles to dynamically load assemblies at runtime. Passing arguments to a method using codedom the asp. The code generated from codedom is no different than that which you generate using an ide like visual studio. I agree to receive these communications from via the means indicated above.
To declare a class, structure, interface, or enumeration using the codedom, create a new codetypedeclaration, and assign it a name. They provide the interface for the true object oriented programming. Csharp codedom parser is a component, which parses csharp source files and produces the codedom compliant syntax tree including comments in code, which are important for code analysis. I have not timed the codedom process, but for small snippets of code it seems pretty fast. Provide definition to the method returns the sum of two numbers. If slang is an automatic transmission, codedomutility is the manual version. Codedom and reflection, so thats the path i choose. Despite the fact that dynamic code generation is surely not the best option to implement such an interface, im still interested in showing how to do it. A simple example that covers why would i need it as a developer, in what scenarios. Codedom example codedom example explanation conclusion about the author.
How to implement inotifypropertychanged with codedom. I was just mingling with codedom namespace and though why not create entity classes which maps to the database table. The example generates a ford focus class type in automobile namespace and the class inherits car class. We face several occasions that we need to generate code by automation. This example demonstrates how to generate source code automatically using. Source code generation example using codedom begeeben. Content management system cms task management project portfolio management time tracking pdf. Although, not something that youre going to use in your daytoday winforms development, the codedom is something that i wanted to bring to peoples attention. The code samples used in this post come from a project i wrote that allowed me to copypaste parts of a customer spec and generate classes that could be used for serialization. Codedom code document object model is a language independent objectmodel which is used for developing automatic source code generators. Sign in sign up instantly share code, notes, and snippets. Imp rove consistency and easeofuse publicly available op erations. With the new version of the language, weve heard a numer of questions about how to use the codedom with the new compiler.
Codetypemember readonly see base class member description. Page 4 the codedom namespace contains classes that abstract the idea of code. So i put together this small piece of code which creates the entity class. A codetypereference can be initialized with a system. Net languages ironpython, ironruby, and other languages passing arguments to a method using codedom. You can design a program that builds a source code model using codedom elements to assemble an object graph. The type of left and right is expressionsyntax, and the type of operatortoken is syntaxtoken.
This post will go over some basics using the codedom. The code you get will construct a codedom compileunit, and it will definitely be ugly. It is also intended to serve as a quick reference of common tasks when coding against codedom. All of the codedom classes support manual creation of instances and assignment of child objects. Comments gets the comment collection for the type member. Can you explain very briefly what codedom is and used for with a simple real life example. Codetypemember readwrite see base class member description. Codedom namespace, provides a nice suite of tools for the latter. T code graph aj c ehcrilarciah rcsu turesrtuc rrgs epesnretsr rkp giolc snp trcuersut le nz. Its not very obvious what features are or are not supported unless you try something and see red squiggles from intellisense.
If you use the codedom, heres an indispensable package to make it awesome. For example, an ifstatementsyntax has an optional elseclausesyntax. Create a console application that will use codedom code to generate the source code for a class. For example, a binaryexpressionsyntax node class has three additional properties specific to binary operators. However, the msdn library does not properly document it, it does not live. Codedom namespace is simply amazing, it lets you to write language specific code. Hi john, you are right the parser is not exposed to the general public but it is. Net framework provides the icodecompiler compiler execution interface. I wanted to share the sample i wrote with everyone so that it can be helpful for people getting introduced to this powerful technology. Moreover, it has a plugin architecture that allows you to disassemble to any language for which you have a plugin, or are prepared to write one. Several tools do exist in order to automate the code generation.
922 669 593 437 1267 669 903 370 989 1199 1128 96 1201 1095 1187 814 103 767 185 237 368 716 974 423 1397 1352 858 677 321 714 846 196 419 151 482 717