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C# Quick Actions and Refactorings

Visual Studio Code gives you many ways to refactor your source code as well as Quick Fixes to generate code and fix issues while you're coding. To access them, click on the 'light bulb' icon that appears or use the commandQuick Fix command⌘. (Windows, LinuxCtrl+.) to display a list of Quick Fixes and refactoring options. You can also right-click the editor and selectRefactor⌃⇧R (Windows, LinuxCtrl+Shift+R) to only display refactoring options.

Supported refactorings and Quick Fixes

Add await

What: Addsawait keyword to a function call.

When: When you're calling a function within an asynchronous method.

How-to:

  1. Place carat by the function call (will most likely be underlined in red).
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectAddawait.

Add await example

Add constructor parameters from members

What: Generate a new constructor with parameters based on selected class members.

When: You introduce a new constructor and want to properly declare it automatically with all the correct parameters.

Why: You could declare the constructor before using it, however this feature generates it automatically.

How-to:

  1. Highlight the class members you want to add as parameters in the constructor.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectGenerate constructor <classname>(<membertype>, <membertype>, <etc.>).

Add constructor parameters from members example

Add DebuggerDisplay attribute

What: TheDebuggerDisplay Attribute controls how an object, property, or field is displayed in the debugger variable windows.

When: You want topin properties within the debugger programmatically in your code.

Why: Pinning properties allows you to quickly inspect objects by their properties by bubbling up that property to the top of the object's property list within the debugger.

How-to:

  1. Place your cursor on either a type, delegate, property, or field.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu and selectAddDebuggerDisplay attribute.
  3. TheDebuggerDisplay attribute is added along with an auto method that returns the defaultToString().

Add DebuggerDisplay attribute example

Add explicit cast

What: Lets you automatically add an explicit cast to an expression, based on usage.

When: You need to add an explicit cast to an expression and want to properly assign it automatically.

Why: You could add an explicit cast to an expression manually, however this feature adds it automatically based on the code context.

How-to:

  1. Place your caret on the error.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectAdd explicit cast.

Add file header

What: Add file headers to existing files, projects, and solutions using anEditorConfig.

When: You want to easily add a file header to files, projects, and solutions.

Why: Your team requires you to include a file header for copyright purposes.

How-to:

  1. Add anEditorConfig to a project or solution if you do not already have one.
  2. Add the following rule to your EditorConfig file:file_header_template.
  3. Set the value of the rule to equal the header text you would like applied. You can use{fileName} as a placeholder for the file name.
  4. Place your caret on the first line of any C# file.
  5. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  6. SelectAdd file header.

Add missing usings / imports

What: Lets you immediately add the necessary imports or using directives for copy-and-pasted code.

When: It's common practice to copy code from different places in your project or other sources and paste it into new code. This Quick Action finds missing imports directives for copy-and-pasted code and then prompts you to add them. This code fix can also add references from project to project.

Why: Because the Quick Action automatically adds necessary imports, you don't need to manually copy the using directives that your code needs.

How-to:

  1. Copy code from a file and paste it into a new one without including the necessary using directives. The resulting error is accompanied by a code fix that adds the missing using directives.
  2. Select⌘. (Windows, LinuxCtrl+.)to open theQuick Actions and Refactorings menu.
  3. SelectUsing <your reference> to add the missing reference.

Add missing  / imports example

Add named argument

What: Append a named argument to the specified parameter value in a function call.

When: If you have a method with a lot of parameters, you can add named arguments to make your code more readable.

How-to:

  1. Place your cursor in a parameter within your function call.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectAdd argument name <parameter name>.

Add named argument example

Convert anonymous type to class

What: Convert an anonymous type to class.

When: You have an anonymous type that you want to continue to build on in a class.

Why: Anonymous types are useful if you're only using them locally. As your code grows, it's nice to have an easy way to promote them to a class.

How-to:

  1. Place your cursor in an anonymous (var) type.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectConvert to class.

Convert anonymous type to class example

Convert between auto property and full property

What: Convert between an auto-implemented property to a full property.

When: The logic of the property has changed.

Why: You can convert between an auto-implemented property to a full property manually, however this feature will automatically do the work for you.

How-to:

  1. Place your cursor on the property name.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. Select from the following two options:

SelectConvert to full property.

Convert to full property example

SelectUse auto property.

Use auto property example

Convert between direct cast and 'as' expression

What: Convert a variable between a regular cast and a try cast using theas keyword.

When: When you expect the cast to fail under certain scenarios (as) or if you never expect the cast to fail (direct cast).

How-to:

  1. Place your cursor on the variable.
  2. Press⌘. (Windows, LinuxCtrl+.) to trigger theQuick Actions and Refactorings menu.
  3. Select from the following two options:

SelectChange to cast.

Change to cast example

SelectChange toas expression.

Change to  expression example

Convert between for loop and foreach statement

What: If you have afor loop in your code, you can use this refactoring to convert it to aforeach statement.

Why: Reasons you might want to convert a for loop to a foreach statement include:

  • You don't use the local loop variable inside the loop except as an index to access items.
  • You want to simplify your code and reduce the likelihood of logic errors in the initializer, condition, and iterator sections.

Reasons you might want to convert a foreach statement to a for loop include:

  • You want to use the local loop variable inside the loop for more than just accessing the item.
  • You are iterating through a multi-dimensional array and you want more control over the array elements.

How-to:

  1. Place your caret in theforeach orfor keyword.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. Select from the following two options:

SelectConvert tofor.

Convert to  example

SelectConvert toforeach.

Convert to

Convert between Get method and property

Convert Get method to property

What: Lets you convert a Get method into a property (and optionally your Set method).

When: You have a Get method that does not contain any logic.

How-to:

  1. Place your cursor in your Get method name.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. (Optional) If you have a Set method, you can also convert your Set method at this time. SelectReplace <Get method or Set method name> with property.

Replace Get method with property example

Convert property to Get method

What: Lets you convert a property to a Get method

When: You have a property that involves more than immediately setting and getting a value

How-to:

  1. Place your cursor in your Get method name.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectReplace <property name> with method.

Replace property name with method example

Convert between if and switch statements

What: Convert anif statement to aswitch statement or to the C# 8.0switch expression.

When: You want to convert anif statement to aswitch statement or aswitch expression and vice versa.

Why: If you are using anif statement, this refactoring enables an easy transition to switch statements or switch expressions.

How-to:

  1. Place your cursor in theif keyword.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. Select from the following options:

SelectConvert toswitch statement.

Convert to  statement example

SelectConvert toswitch expression.

Convert to  expression example

SelectConvert toif statement.

Convert to  statement example

Convert between regular string and verbatim string

What: Lets you convert between regular string and verbatim string literals.

When: You either want to save space or provide more clarity in your code.

Why: Converting a verbatim string literal to a regular string literal can help save space. Converting a regular string literal to a verbatim string literal can provide more clarity.

How-to:

  1. Place your caret on either the regular string or verbatim string literal:
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. Select from one of the following options:

SelectConvert to regular string.

SelectConvert to verbatim string.

Convert class to record

What: Convert your class to a C# record.

When: When you want to quickly change your class to a record, which is tailored for storing data and immutability.

How-to:

  1. Place your cursor on the class name.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectConvert to positional record.

Convert class to record before example

Convert class to record after example

Convert local function to method

What: Convert a local function to a method.

When: You have a local function that you want to define outside your current local context.

Why: You want to convert a local function into a method so that you can call it outside your local context. You might want to convert to a method when your local function is getting too long. When you define the function in a separate method, your code is easier to read.

How-to:

  1. Place your cursor in the local function.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectConvert to method.

Convert local function to method example

Convert numeric literal to hex, decimal, or binary number

What: Convert a number between a hexadecimal, binary, or decimal number.

When: Use when you want to automatically convert a number to the desired base without having to manually calculate the conversion.

How-to:

  1. Place your cursor on the numeric literal.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. Select one of the following options:

SelectConvert to decimal.

Convert to decimal example

SelectConvert to hex.

Convert to hex example

SelectConvert to binary.

Convert to binary example

Convert placeholder to interpolated string

What: Convert aString.Format formatted result string (or placeholder) to an interpolated string.

When: Use when you want to an interpolated string quickly.

Why: Interpolated strings can give you a more readable version ofString.Format and can let you access your variable name directly.

How-to:

  1. Place your cursor on theString.Format placeholder.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectConvert to interpolated string.

Convert placeholder to interpolated string example

Convert regular string to interpolated string

What: Change a regular string to an interpolated string.

When: Use when you want to clean up your code and make it more readable.

How-to:

  1. Place your cursor on the string you want to convert.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectConvert to interpolated string.

Convert to interpolated string before example

Convert to interpolated string after example

Convert tuple to struct

What: Convert your tuple to astruct

When: Use when want to quickly change your tuple to astruct and want to have fixed data you want to access multiple times.

How-to:

  1. Place your cursor on the tuple.

  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.

  3. Select one of the following options:

    • SelectConvert tostruct -> updating usages in containing member
    • SelectConvert tostruct -> updating usages in containing type
    • SelectConvert tostruct -> updating usages in containing project
    • SelectConvert tostruct -> updating usages in dependent projects

Convert tuple to  options

Convert tuple to  example

Encapsulate field

What: Lets you turn a field into a property, and update all usages of that field to use the newly created property.

When: You want to move a field into a property, and update all references to that field.

Why: You want to give other classes access to a field, but don't want those classes to have direct access. By wrapping the field in a property, you could write code to verify the value being assigned, for example.

How-to:

  1. Place your cursor inside the name of the field to encapsulate.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. Select one of the following:

SelectEncapsulate field: <fieldname> (and use property).

Encapsulate field and use property example

SelectEncapsulate field: <fieldname> (but still use field).

Encapsulate field but still use field example

Generate comparison operators

What: Lets you generate Comparison operators for types that implementIComparable.

When: You have a type that implementsIComparable we will automatically add the comparison operators.

Why: If you are implementing a value type, you should consider overriding theEquals method to gain increased performance over the default implementation of theEquals method onValueType.

How-to:

  1. Place your cursor either inside the class or on the IComparable keyword.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectGenerate comparison operators from the drop-down menu.

Generate default constructors

What: Lets you immediately generate the code for a new default constructor on a class.

When: You introduce a new default constructor and want to properly declare it automatically.

Why: You could declare the constructor before using it, however this feature generates it automatically.

How-to:

  1. Place your cursor on the class name.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectGenerate constructor <classname>().

Generate default constructor example

Generate parameter

What: Automatically generates a method parameter.

When: You reference a variable in a method that doesn't exist in the current context and receive an error; you can generate a parameter as a code fix.

Why: You can quickly modify a method signature without losing context.

How-to:

  1. Place your cursor in the variable name.
  2. Press⌘. (Windows, LinuxCtrl+.) to trigger theQuick Actions and Refactorings menu.
  3. SelectGenerate parameter.

Generate parameter example

Implement all members explicitly

What: Define your interface's methods explicitly in a class. An explicit interface implementation is a class member that is only called through the specified interface.

When: Use when:

  • You don't want the same implementation to be called for multiple interfaces.
  • You want to resolve cases where two interfaces each declare different members of the same name such as a property and a method.

How-to:

  1. Place your cursor on an interface being implemented in a class.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectImplement all members explicitly:

Implement all members explicitly example

Implement all members implicitly

What: Define your interface's methods implicitly in a class. An implicit interface implementation is when an interface's methods and properties are directly added to the class as public methods.

How-to:

  1. Place your cursor on an interface being implemented in a class.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectImplement interface:

Implement all members implicitly

Inline method

What: Inline method refactoring.

When: You want to replace usages of a static, instance, and extension method within a single statement body with an option to remove the original method declaration.

Why: This refactoring provides a clearer syntax.

How-to:

  1. Place your caret on the usage of the method.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. Select from one of the following options:

SelectInline <QualifiedMethodName> to remove the inline method declaration:

Inline method example

SelectInline and keep <QualifiedMethodName> to preserve the original method declaration:

Inline and keep method example

Inline temporary variable

What: Lets you remove a temporary variable and replace it with its value instead.

When: The use of the temporary variable makes the code harder to understand.

Why: Removing a temporary variable may make the code easier to read.

How-to:

  1. Place your cursor inside the temporary variable to be inlined.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectInline temporary variable.

Inline temporary variable example

Introduce local variable for expression

What: Lets you immediately generate a local variable to replace an existing expression.

When: You have code that could be easily reused later if it were in a local variable.

Why: You could copy and paste the code multiple times to use it in various locations, however it would be better to perform the operation once, store the result in a local variable, and use the local variable throughout.

How-to:

  1. Place your caret on the expression that you want to assign to a new local variable.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. Select from the following options:

SelectIntroduce local -> Introduce local for <expression>

Introduce local for expression example

SelectIntroduce local -> Introduce local for all occurrences of <expression>

Introduce parameter

What: Lets you immediately generate a new parameter to replace an existing expression.

When: You have code that could be easily reused later if it were in a parameter.

Why: You could copy and paste the code multiple times to use it in various locations, however it would be better to perform the operation once, store the result in a parameter, and use the parameter throughout.

How-to:

  1. Place your caret on the expression that you want to assign to a new parameter.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. Select from the following options:

SelectIntroduce parameter for <expression> -> and update call sites directly

Update call sites directly example

SelectIntroduce parameter for <expression> -> into extracted method

Introduce parameter into extracted method example

SelectIntroduce parameter for <expression> -> into new overload

Introduce parameter into new overload example

Introduceusing statement

What: Add ausing statement / code block to yourIDisposable instance.

When: You have anIDisposable instance that you want to ensure is acquired, used, and disposed correctly.

How-to:

  1. Place your caret on the expression that you want to assign to a new parameter.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectIntroduceusing statement.

Introduce  statement example

Invert conditional expressions and logical operations

What: Lets you invert a conditional expression or a conditionaland \or operator.

When: You have a conditional expression or conditionaland \or operator that would be better understood if inverted.

Why: Inverting an expression or conditionaland \or operator by hand can take much longer and possibly introduce errors. This code fix helps you do this refactoring automatically.

How-to:

  1. Place your cursor in a conditional expression or a conditionaland \or operator.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectInvert conditional orReplace&& with||

Invert conditional example

Replace  with  example

Invert if

What: Lets you invert anif orif else statement without changing the meaning of the code.

When: When you have anif orif else statement that would be better understood when inverted.

Why: Inverting anif orif else statement by hand can take much longer and possibly introduce errors. This code fix helps you do this refactoring automatically.

How-to:

  1. Place your cursor in anif orif else statement.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectInvertif.

Invert  example

Make member static

What: Make a member static.

When: You want a non-static member to be static.

Why: Static members improve readability: knowing that specific code is isolated makes it easier to understand, reread, and reuse.

How-to:

  1. Place your caret on the member name.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectMake static.

Make member static example

Move declaration near reference

What: Lets you move variable declarations closer to their usage.

When: You have variable declarations that can be in a narrower scope.

Why: You could leave it as it is, but that may cause readability issues or information hiding. This is a chance to refactor to improve readability.

How-to:

  1. Place your cursor in the variable declaration.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectMove declaration near reference.

Move declaration near reference example

Move type to matching file

What: Lets you move the selected type to a separate file with the same name.

When: You have multiple classes, structs, interfaces, etc. in the same file that you want to separate.

Why: Placing multiple types in the same file can make it difficult to find these types. By moving types to files with the same name, code becomes more readable and easier to navigate.

How-to:

  1. Place the cursor inside the name of the type where it is defined.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectMove type to <typename>.cs.

Move type to matching file example

Reverse for statement

What: Lets you invert afor statement.

When: Use when you want to reverse the meaning of afor statement and how it iterates.

Why: Inverting afor statement by hand can take much longer and possibly introduce errors. This code fix helps you do this refactoring automatically.

How-to:

  1. Place your cursor in thefor statement.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectReversefor statement.

Reverse  statements example

Split or merge if statements

What: Split or mergeif statements.

When: You want to split anif statement that uses the&& or|| operators into a nestedif statement, or merge anif statement with an outerif statement.

Why: It's a matter of style preference.

How-to:

If you want to split theif statement:

  1. Place your cursor in theif statement by the&& or|| operator.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectSplit into nestedif statements.

Split into nested  statements example

If you want to merge the innerif statement with the outerif statement:

  1. Place your cursor in the innerif keyword.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectMerge with nestedif statement.

Merge with nested  statements example

Use explicit type

What: Use this refactoring to replacevar in a local variable declaration with an explicit type.

Why: To improve the code's readability or when you don't want to initialize the variable in the declaration.

However,var must be used when a variable is initialized with an anonymous type and the properties of the object are accessed at a later point. For more information, seeImplicitly typed local variables (C#).

How-to:

  1. Place the caret on thevar keyword.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectUse explicit type instead ofvar.

Use explicit type instead of  example

Use implicit type

What: Use this refactoring to replace an explicit type in a local variable declaration withvar.

Why: To fit your personal coding conventions and to have less code displayed.Var must be used when a variable is initialized with an anonymous type and the properties of the object are accessed at a later point. For more information, seeImplicitly typed local variables (C#).

How-to:

  1. Place the caret on the explicit type keyword.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectUse implicit type.

Use implicit type example

Use lambda expression or block body

What: Lets you refactor a lambda expression to use an expression body or a block body.

When: You prefer lambda expressions to use either an expression body or a block body.

Why: Lambda expressions can be refactored to improve readability according to your user preference.

How-to:

  1. Place your cursor on the right of a lambda operator.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. Select one of the following:

SelectUse block body for lambda expressions.

Use block body for lambda expressions example

SelectUse expression body for lambda expressions.

Use expression body for lambda expressions

Use recursive patterns

What: Converts a code block to using a recursive pattern. This refactoring works with switch statements, property pattern matching, tuple pattern matching, and positional pattern matching.

When: Using recursive patterns can make your code more readable / cleaner.

How-to:

  1. Place your cursor on the expression you want to convert to a recursive pattern.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. Select one of the following:

SelectConvertswitch statement to expression.

Convert  statement to expression example

SelectUse recursive patterns.

Use recursive patterns before example

Use recursive patterns after example

Wrap, indent, and align refactorings

Wrap and align call chains

What: Lets you wrap and align chains of method calls.

When: You have a long chain consisting of several method calls in one statement.

Why: Reading a long list is easier when they're wrapped or indented according to user preference.

How-to:

  1. Place your cursor in any of the call chains.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectWrap call chain orWrap and align call chain to accept the refactoring.

Wrap and align call chain example

Wrap, indent, and align parameters or arguments

What: Lets you wrap, indent, and align parameters or arguments.

When: You have a method declaration or call that has multiple parameters or arguments.

Why: Reading a long list of parameters or arguments is easier when they're wrapped or indented according to user preference.

How-to:

  1. Place your cursor in a parameter list.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. Select from the following options:

SelectWrap every parameter -> Align wrapped parameters

Align wrapped parameters example

SelectWrap every parameter -> Indent all parameters

Indent all parameters example

SelectWrap every parameter -> Indent wrapped parameters

Indent wrapped parameters example

Wrap binary expressions

What: Lets you wrap binary expressions.

When: You have a binary expression.

Why: Reading a binary expression is easier when it is wrapped to user preference.

How-to:

  1. Place your cursor in the binary expression.
  2. Press⌘. (Windows, LinuxCtrl+.)to trigger theQuick Actions and Refactorings menu.
  3. SelectWrap expression to accept the refactoring.

Wrap expression example

6/6/2023

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