@@ -8,20 +8,30 @@ This includes design-time support, such that code generation can respond to
88changes made in hand-authored code files by generating new code that shows
99up to Intellisense as soon as the file is saved to disk.
1010
11+ ## Table of Contents
12+
13+ * [ How to write your own code generator] [ ]
14+ * [ Apply code generation] [ ]
15+ * [ Developing your code generator] [ ]
16+ * [ Packaging up your code generator for others' use] [ ]
17+
1118## How to write your own code generator
19+ [ How to write your own code generator ] : #how-to-write-your-own-code-generator
1220
1321In this walkthrough, we will define a code generator that replicates any class
1422your code generation attribute is applied to, but with a suffix appended to its name.
1523
1624### Define code generator
25+ [ Define code generator ] : #define-code-generator
1726
18- This must be done in a library that targets netstandard1.5 or net462 (or later).
27+ This must be done in a library that targets netstandard1.6 or net461 (or later;
28+ net461 is supported if you have .NET Core SDK v2.0+ installed, [ see docs for details] [ netstandard-table ] ).
1929Your generator cannot be defined in the same project that will have code generated
2030for it because code generation runs * before* the receiving project is itself compiled.
2131
2232Install the [ CodeGeneration.Roslyn] [ NuPkg ] NuGet Package.
2333
24- Define the generator class:
34+ Define the generator class ( * note: constructor accepting ` AttributeData ` parameter is required * ) :
2535
2636``` csharp
2737using CodeGeneration .Roslyn ;
@@ -67,7 +77,7 @@ public class DuplicateWithSuffixGenerator : ICodeGenerator
6777To activate your code generator, you need to define an attribute that can be
6878applied to the class to be copied. This attribute may be defined in the same
6979assembly as defines your code generator, but since your code generator must
70- be defined in a netstandard1.3 or net46 library, this may limit which projects
80+ be defined in a netstandard1.6+ or net461+ library, this may limit which projects
7181can apply your attribute. So define your attribute in another assembly if
7282it must be applied to projects that target older platforms.
7383
@@ -76,7 +86,7 @@ If your attributes are in their own project, you must install the
7686
7787Define your attribute class.
7888For this walkthrough, we will assume that the attributes are defined in the same
79- netstandard1.3 project that defines the generator which allows us to use the more
89+ netstandard1.6 project that defines the generator which allows us to use the more
8090convenient ` typeof ` syntax when declaring the code generator type.
8191If the attributes and code generator classes were in separate assemblies, you must
8292specify the assembly-qualified name of the generator type as a string instead.
@@ -110,10 +120,13 @@ instead as just a compile-time hint to code generation, and allowing you to not
110120with a dependency on your code generation assembly.
111121
112122## Apply code generation
123+ [ Apply code generation ] : #apply-code-generation
113124
114125The attribute may not be applied in the same assembly that defines the generator.
115126This is because the code generator must be compiled in order to execute before compiling
116- the project that applies the attribute.
127+ the project that applies the attribute. Also, the consuming project (where the code
128+ will be generated) must use SDK-style csproj, which implies using VS2017+ or ` dotnet `
129+ CLI tooling (VS Code with omnisharp, for example).
117130
118131Applying code generation is incredibly simple. Just add the attribute on any type
119132or member supported by the attribute and generator you wrote. Note you will need to
@@ -128,7 +141,14 @@ public class Foo
128141
129142Install the [ CodeGeneration.Roslyn.BuildTime] [ BuildTimeNuPkg ] package into the
130143project that uses your attribute. You may set ` PrivateAssets="all" ` on this reference
131- because this is a build-time only package.
144+ because this is a build-time only package. You must also add this item to an ` <ItemGroup> ` in the project
145+ that will execute the code generator as part of your build:
146+
147+ ``` xml
148+ <DotNetCliToolReference Include =" dotnet-codegen" Version =" 0.4.12" />
149+ ```
150+
151+ You should adjust the version in the above xml to match the version of this tool you are using.
132152
133153You can then consume the generated code at design-time:
134154
@@ -146,43 +166,23 @@ If you execute Go To Definition on it, Visual Studio will open the generated cod
146166that actually defines ` FooA ` , and you'll notice it's exactly like ` Foo ` , just renamed
147167as our code generator defined it to be.
148168
149- ### Using ` dotnet build `
150-
151- If you build with ` dotnet build ` , you need to take a couple extra steps. First, define a ` nuget.config ` file with an extra package source:
152-
153- ``` xml
154- <?xml version =" 1.0" encoding =" utf-8" ?>
155- <configuration >
156- <packageSources >
157- <add key =" api.nuget.org" value =" https://api.nuget.org/v3/index.json" />
158- <add key =" corefxlab" value =" https://dotnet.myget.org/F/dotnet-corefxlab/api/v3/index.json" />
159- </packageSources >
160- </configuration >
161- ```
162-
163- Second, add this item to an ` <ItemGroup> ` in the project that will execute the code generator as part of your build:
164-
165- ``` xml
166- <DotNetCliToolReference Include =" dotnet-codegen" Version =" 0.4.12" />
167- ```
168-
169- You should adjust the version in the above xml to match the version of this tool you are using.
170-
171169### Shared Projects
172170
173171When using shared projects and partial classes across the definitions of your class in shared and platform projects:
174172
175173* The code generation attributes should be applied only to the files in the shared project
176174 (or in other words, the attribute should only be applied once per type to avoid multiple generator invocations).
177- * The MSBuild: GenerateCodeFromAttributes custom tool must be applied to every file we want to auto generate code from.
175+ * The ` MSBuild:GenerateCodeFromAttributes ` custom tool must be applied to every file we want to auto generate code from.
178176
179177## Developing your code generator
178+ [ Developing your code generator ] : #developing-your-code-generator
180179
181180Your code generator can be defined in a project in the same solution as the solution with
182181the project that consumes it. You can edit your code generator and build the solution
183182to immediately see the effects of your changes on the generated code.
184183
185184## Packaging up your code generator for others' use
185+ [ Packaging up your code generator for others' use ] : #packaging-up-your-code-generator-for-others-use
186186
187187You can also package up your code generator as a NuGet package for others to install
188188and use. Your NuGet package should include a dependency on the ` CodeGeneration.Roslyn.BuildTime `
@@ -210,7 +210,7 @@ For example your package should have a `build\MyPackage.targets` file with this
210210Then your package should also have a ` tools ` folder that contains your code generator and any of the runtime
211211dependencies it needs * besides those delivered by the ` CodeGeneration.Roslyn.BuildTime ` package* .
212212
213- Your attributes assembly should be placed under your package's ` lib ` folder` so consuming projects
213+ Your attributes assembly should be placed under your package's ` lib ` folder so consuming projects
214214can apply those attributes.
215215
216216Your consumers should depend on your package, and the required dotnet CLI tool,
@@ -223,21 +223,10 @@ so that the MSBuild Task can invoke the `dotnet codegen` command line tool:
223223</ItemGroup >
224224```
225225
226- Also, any consumer must have a nuget.config file with at least this content:
227-
228- ``` xml
229- <?xml version =" 1.0" encoding =" utf-8" ?>
230- <configuration >
231- <packageSources >
232- <add key =" api.nuget.org" value =" https://api.nuget.org/v3/index.json" />
233- <add key =" corefxlab" value =" https://dotnet.myget.org/F/dotnet-corefxlab/api/v3/index.json" />
234- </packageSources >
235- </configuration >
236- ```
237-
238226Make sure that the DotNetCliToolReference version matches the version of the
239227` CodeGeneration.Roslyn ` package your package depends on.
240228
241229[ NuPkg ] : https://nuget.org/packages/CodeGeneration.Roslyn
242230[ BuildTimeNuPkg ] : https://nuget.org/packages/CodeGeneration.Roslyn.BuildTime
243231[ AttrNuPkg ] : https://nuget.org/packages/CodeGeneration.Roslyn.Attributes
232+ [ netstandard-table ] : https://docs.microsoft.com/dotnet/standard/net-standard#net-implementation-support
0 commit comments