JetBrains Rider 2018.2 Help

Typing Assistance

In addition to saving your time by providing smart suggestions in completion lists, JetBrains Rider provides other typing assistance features, which let you create and edit your code even faster.

Auto-Inserting Matching Delimiters

By default, whenever you type an opening delimiter (, [, ", or ', a paired character is inserted automatically (whenever appropriate). If you change your mind and press Backspace to delete an opening delimiter, its closing pair is also deleted. If the pairing closing delimiter already exists, JetBrains Rider will not add another one. The matching symbols are inserted according to your formatting preferences.

Regarding braces {}, JetBrains Rider can provide a closing brace immediately on typing the opening one, or on pressing Enter.

If necessary, you can change the default behavior. To do so, go to the the Editor | General | Typing Assistance page of JetBrains Rider settings (Ctrl+Alt+S) and use the controls in the Braces and Parentheses section.

Correcting Length/Count mistyping

JetBrains Rider prevents you from stumbling over mistyped Length/Count properties of arrays/collections. As soon as you erroneously start typing the Count property for a usage of an array, JetBrains Rider will allow you to pick it from the completion list and replace with the Length property, which you probably meant to type.

Completing mistyped Count property for array

In a similar way, it will help you call the Count property on a collection usage when you start typing the Length property by mistake.

Completing mistyped Length property for collection

The correct property will be there as soon as you accept the completion suggestion:

void Foo(int[] array, List<int> collection) { if(array.Length == collection.Count }

Generating equality and flag checks for enumeration types

When you need to compare a value of enum type to one of the members of this enum, just type a dot and then pick the desired enum member in the completion list:

Completing enum members to produce equality/flag checks

JetBrains Rider will generate the comparison for you:

public enum Direction { North, East, South, West } void Turn(Direction whereTo) { if(whereTo == Direction.South }

Creating type parameter from usage in method parameters

When creating generic methods, you can easily add type parameters by typing T for a new parameter and choosing the corresponding item in the completion list

Creating type parameter from usage in method parameters

JetBrains Rider will add a new type parameter to the method declaration and bring you to a position where you can type the name of the type parameter in both its declaration and usage:

Creating type parameter from usage in method parameters

After you finish typing the name, press Enter or Tab to go on typing.

Adding NotNull/CanBeNull annotations

If code annotations support is enabled in your project, you can add [NotNull] and [CanBeNull] annotations, as well as generate null checks with a single keystroke:

  • When writing a method signature or member declaration, type ! or ? directly after the type name to get the item annotated with [NotNull] or [CanBeNull]:

  • If the symbol is already annotated with [NotNull] or [CanBeNull], you can type ? or ! correspondingly to change the existing annotation.

  • If a parameter is marked with the [NotNull] attribute, you can set the caret directly after the parameter name or parameter type and press !:

    private void Foo([NotNull] object/*!*/ arg/*!*/)
    JetBrains Rider will generate a null check for this parameter. You can configure the null-check pattern on the Code Editing | C# | Null Checking page of JetBrains Rider settings (Ctrl+Alt+S).

By default, typing assist for [NotNull] or [CanBeNull] is enabled. If you want to disable it, clear the Annotate nullability... check-boxes on the Environment | Editor | Editor Behavior page of JetBrains Rider settings (Ctrl+Alt+S).

Making comments multiline on Enter

Block comments

If you write a multiline block comment (/*....*/), you can type the opening part /*, then write the first line, and the just hit Enter in the end of the line — JetBrains Rider will insert the closing part */.

Additionally, JetBrains Rider will insert the asterisk * in the beginning of each line of a block comment as you press Enter. This behavior is enabled by default, but you can turn it off by clearing the Insert * on Enter after /* check box on the Editor | General | Typing Assistance page of JetBrains Rider settings (Ctrl+Alt+S).

Line comments

In simple (non-XML Doc) line comments, you can also press Enter in the middle of the comment text, and to avoid getting a non-compilable text on the new line, JetBrains Rider will automatically add two slashes (//) in front of the text. If you press Enter at the end of the comment line, you will start an empty new line as usual.

Wrapping code blocks with braces and parentheses

With JetBrains Rider, you can select a code block or an expression, then type an opening { or a closing } brace to put the selection inside braces, or type an opening ( or a closing ) parenthesis to put the selection inside parentheses. To enable or disable this behavior, use the Surround selection on typing a brace or parenthesis check box on the Editor | General | Typing Assistance page of JetBrains Rider settings (Ctrl+Alt+S).

Last modified: 4 October 2018

See Also