Typing Assistance
In addition to saving your time by providing smart suggestions in completion lists, ReSharper 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, ReSharper will not add another one. The matching symbols are inserted according to your formatting preferences.
Regarding braces {}, ReSharper 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 page of ReSharper options and use the controls in the Braces and Parentheses section.
Correcting Length/Count mistyping
ReSharper 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, ReSharper will allow you to pick it from the completion list and replace with the Length property, which you probably meant to type.
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.
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:
ReSharper 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
ReSharper 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:
After you finish typing the name, press Enter or Tab to go on typing.
Smart behaviour of dot and semicolon
By default, when you choose a method in the completion list ReSharper automatically adds parentheses and sets your caret between them in the position to start typing arguments. If you want to call the method without parameters, and chain-call another method, you can type the dot right where your caret is and ReSharper will move it to the right place:
myStringBuilder.AppendLine(./*caret*/) becomes myStringBuilder.AppendLine()./*caret*/
If you just typed a complete method call, and then decide to chain-call another method, you do not have to move your caret, just type the dot right after the final semicolon:
myStringBuilder.AppendLine();./*caret*/ becomes myStringBuilder.AppendLine()./*caret*/;
When you caret is inside parentheses, you do not have to move it outside to type the final semicolon, just type it right away or after the last argument:
myStringBuilder.AppendLine("line";/*caret*/) becomes myStringBuilder.AppendLine("line");/*caret*/
Correcting prefixes in verbatim string interpolation
Starting from C# 6.0, you can make the same string both interpolated and verbatim provided that you add the $ and @ prefixes in the correct order: $@"some string".
With ReSharper, the order will be always correct - a mistakenly typed @$ will be automatically replaced with the correct $@.
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 !: ReSharper will generate a null check for this parameter. You can configure the null-check pattern on the page of ReSharper options.
private void Foo([NotNull] object/*!*/ arg/*!*/)
By default, typing assist for [NotNull] or [CanBeNull] is enabled. If you want to disable it, clear the Annotate nullability... check-boxes on the page of ReSharper options.
Converting expression-bodied to block-bodied members
When typing { after => in an expression-bodied member, ReSharper will convert it into a block body:
Virtual indents for empty lines
ReSharper helps you avoid trailing whitespaces and at the same time have your caret in the position to start typing. When you press Enter, ReSharper does not insert indent characters, however it sets the caret according to the indent calculated for this line. As soon as you start typing, ReSharper automatically inserts the indent characters (which could be whitespaces, tabs, or a mix of both, depending on the settings) so that your code stays properly formatted.
This feature is called with virtual indents and it is enabled by default, and unless you opted to display white spaces in the editor (), you will not even notice it.
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 — ReSharper will insert the closing part */.
Additionally, ReSharper 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 page of ReSharper options. Even if this option is enabled, you can press Shift+Enter to add a new line without the leading asterisk.
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, ReSharper 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 ReSharper, 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 page of ReSharper options.