How to reference generic classes and methods in xml documentation

C# Problem Overview

When writing xml documentation you can use <see cref="something">something</see>, which works of course. But how do you reference a class or a method with generic types?

public class FancyClass<T>
{
  public string FancyMethod<K>(T value) { return "something fancy"; }
}

If I was going to write xml documentation somewhere, how would I reference the fancy class? how can I reference a FancyClass<string>? What about the method?

For example in a different class I wanted to let the user know that I will return an instance of FancyClass<int>. How could I make a see cref thing for that?

C# Solutions

Solution 1 - C#

To reference the method:

/// <see cref="FancyClass{T}.FancyMethod{K}(T)"/> for more information.

Solution 2 - C#

TL;DR:

> "How would I reference FancyClass<T>?"

   /// <see cref="FancyClass{T}"/>

> "What about FancyClass<T>.FancyMethod<K>(T value)?"

   /// <see cref="FancyClass{T}.FancyMethod{K}(T)"/>

> "How can I reference a FancyClass<string>?"

   /// <see cref="SomeType.SomeMethod(FancyClass{string})"/>
   /// <see cref="FancyClass{T}"/> whose generic type argument is <see cref="string"/>

While you can reference a method whose signature includes FancyClass<string> (e.g. as a parameter type), you cannot reference such a closed generic type directly. The second example works around that limitation. (This is seen e.g. on the MSDN refence page for the static System.String.Concat(IEnumerable<string>) method). :

XML documentation comment `cref` rules:

Surround the generic type parameter list with curly braces {} instead of with <> angle brackets. This spares you from escaping the latter as < and > — remember, documentation comments are XML!
If you include a prefix (such as T: for types, M: for methods, P: for properties, F: for fields), the compiler will not perform any validation of the reference, but simply copy the cref attribute value straight to the documentation XML output. For this reason, you'll have to use the special ["ID string" syntax](https://msdn.microsoft.com/en-us/library/fsbx0t7x.aspx "MSDN reference page on XML documentation comment ID strings") that applies in such files: always use fully-qualified identifiers, and use backticks to reference generic type parameters (`n on types, ``n on methods).
If you omit the prefix, regular language naming rules apply: you can drop namespaces for which there's a using statement, and you can use the language's type keywords such as int instead of System.Int32. Also, the compiler will check the reference for correctness.

XML documentation comment `cref` cheat sheet:

namespace X
{
    using System;

    /// <see cref="I1"/>  (or <see cref="X.I1"/> from outside X)
    /// <see cref="T:X.I1"/>
    interface I1
    {
        /// <see cref="I1.M1(int)"/>  (or <see cref="M1(int)"/> from inside I1)
        /// <see cref="M:X.I1.M1(System.Int32)"/>
        void M1(int p);

        /// <see cref="I1.M2{U}(U)"/>
        /// <see cref="M:X.I1.M2``1(``0)"/>
        void M2<U>(U p);

        /// <see cref="I1.M3(Action{string})"/>
        /// <see cref="M:X.I1.M3(System.Action{System.String})"/>
        void M3(Action<string> p);
    }

    /// <see cref="I2{T}"/>
    /// <see cref="T:X.I2`1"/>
    interface I2<T>
    {
        /// <see cref="I2{T}.M1(int)"/>
        /// <see cref="M:X.I2`1.M1(System.Int32)"/>
        void M1(int p);

        /// <see cref="I2{T}.M2(T)"/>
        /// <see cref="M:X.I2`1.M2(`0)"/>
        void M2(T p);

        /// <see cref="I2{T}.M3{U}(U)"/>
        /// <see cref="M:X.I2`1.M3``1(``0)"/>
        void M3<U>(U p);
    }
}

Solution 3 - C#

/// <summary>Uses a <see cref="FancyClass{T}" /> instance.</summary>

BTW, it was present in the MSDN documentation of .Net Framework 2.0 and 3.0, but it disapeared in the version 3.5

Solution 4 - C#

None of the answers shown so far work completely for me. ReSharper won't convert the see tag into a Ctrl+click-able link (e.g. ) unless it completely resolves.

If the method in the OP were in a namespace called Test, the completely resolved link to the method shown would be:

As you may be able to work out, there should only be one backtick before the number of class type parameters, then two backticks before the number of method type parameters, then the parameters are the zero-indexed parameter with the appropriate number of backticks.

So we can see that FancyClass has one class type parameter, FancyMethod has one type parameter, and an object of the FancyClass parameter type will be passed to the method.

As you can more clearly see in this example:

namespace Test
{
    public class FancyClass<A, B>
    {
        public void FancyMethod<C, D, E>(A a, B b, C c, D d, E e) { }
    }
}

The link becomes:

M:Test.FancyClass`2.FancyMethod``3(`0,`1,``0,``1,``2)

Or "Class with two type parameters which has a method with three type parameters where the method parameters are ClassType1, ClassType2, MethodType1, MethodType2, MethodType3"

As an additional note, I didn't find this documented anywhere and I'm not a genius, the compiler told me all this. All you have to do is create a test project, enable XML documentation, then insert the code you want to work out a link for, and put the start of an XML doc comment on it (///):

namespace Test
{
    public class FancyClass<T>
    {
        ///
        public string FancyMethod<K>(T value) { return "something fancy"; }
    }

    public class Test
    {
        public static void Main(string[] args) { }
    }
}

Then build your project, and the outputted XML documentation includes the link in the doc->members->member element under the attribute name:

<?xml version="1.0"?>
<doc>
	<assembly>
		<name>Test</name>
	</assembly>
	<members>
		<member name="M:Test.FancyClass`1.FancyMethod``1(`0)">
			
		</member>
	</members>
</doc>

Solution 5 - C#

Further from the answers by Lasse and T.B.C:

/// <see cref="T:FancyClass`1{T}"/> for more information.

/// <see cref="M:FancyClass`1{T}.FancyMethod`1{K}(T)"/> for more information.

will also provide tooltips correctly, whereas their version renders it with the curly braces.

Solution 6 - C#

/// Here we discuss the use of <typeparamref name="TYourExcellentType"/>.
/// <typeparam name="TYourExcellentType">Your exellent documentation</typeparam>

Solution 7 - C#

/// <see cref="FancyClass&lt;T>.FancyMethod&lt;K>(T)"/> for more information.

Solution 8 - C#

Here's an answer I gave somewhere else. It will work for classes and methods too.

I tried everything on stack overflow to a get results that work under several scenarios. Here's a solution that works for me. (That's subjective concerning anyone else.)

Produces clickable links.
Hovering over identifiers works.
Produces .xml file correctly.
Produces no errors in intellisense.
Works for nullable generic type parameters.
Works in Resharper and it's built-in XML Doc window (Resharper -> Edit -> Show Quick Documentation)
Works in XAM Doc Preview for Atomineer Pro Documentaion Visual Studio Extension.
Works with a generic type of a generic type.

Example #1

  /// <summary>
  ///  This instance field holds a reference to the
  ///  <see cref="ConcurrentDictionary{Decimal, Boolean}"/> as
  ///  <see cref="T:ConcurrentDictionary&lt;decimal, bool?&gt;"/> that contains
  ///  the list of all PDF's that are currently opened and being displayed.
  /// </summary>
  private ConcurrentDictionary<decimal, bool?> openedPdfs = default!;

  Note: 
    The ConcurrentDictionary{Decimal, Boolean} will correctly produce a
    clickable link of ConcurrentDictionary{TKey, TValue} on hovering while
    T:ConcurrentDictionary&lt;decimal, bool?&gt; makes sure the reader gets
    information on what type TKey and TValue are.

Example # 2 (using "T")

  /// <summary>
  ///  This instance field holds a reference to the
  ///  <see cref="ConcurrentDictionary{TKey, TValue}"/> as
  ///  <see cref="T:ConcurrentDictionary&lt;decimal, bool?&gt;"/> that contains
  ///  the list of all PDF's that are currently opened and being displayed.
  /// </summary>
  private ConcurrentDictionary<decimal, bool?> openedPdfs = default!;

Content Type	Original Author	Original Content on Stackoverflow
Question	Svish	View Question on Stackoverflow
Solution 1 - C#	Lasse V. Karlsen	View Answer on Stackoverflow
Solution 2 - C#	stakx - no longer contributing	View Answer on Stackoverflow
Solution 3 - C#	thinkbeforecoding	View Answer on Stackoverflow
Solution 4 - C#	MrLore	View Answer on Stackoverflow
Solution 5 - C#	Stephen Drew	View Answer on Stackoverflow
Solution 6 - C#	JohnL4	View Answer on Stackoverflow
Solution 7 - C#	Max Toro	View Answer on Stackoverflow
Solution 8 - C#	K. Carter Sr.	View Answer on Stackoverflow

How to reference generic classes and methods in xml documentation

C# Problem Overview

C# Solutions

Solution 1 - C#

Solution 2 - C#

TL;DR:

XML documentation comment `cref` rules:

XML documentation comment `cref` cheat sheet:

Solution 3 - C#

Solution 4 - C#

Solution 5 - C#

Solution 6 - C#

Solution 7 - C#

Solution 8 - C#

Is there a way to get a collection of all the Models in your Rails app?

Using regular expressions to parse HTML: why not?

Attributions

C# Problem Overview

C# Solutions

Solution 1 - C#

Solution 2 - C#

TL;DR:

XML documentation comment cref rules:

XML documentation comment cref cheat sheet:

Solution 3 - C#

Solution 4 - C#

Solution 5 - C#

Solution 6 - C#

Solution 7 - C#

Solution 8 - C#

Is there a way to get a collection of all the Models in your Rails app?

Using regular expressions to parse HTML: why not?

Attributions

XML documentation comment `cref` rules:

XML documentation comment `cref` cheat sheet: