Use expression body for lambdas (IDE0053)

Property	Value
Rule ID	IDE0053
Title	Use expression body for lambdas
Category	Style
Subcategory	Language rules (expression-bodied members)
Applicable languages	C#
Options	csharp_style_expression_bodied_lambdas

Overview

This style rule concerns the use of expression bodies versus block bodies for lambda expressions.

Options

Options specify the behavior that you want the rule to enforce. For information about configuring options, see Option format.

csharp_style_expression_bodied_lambdas

Property	Value	Description
Option name	csharp_style_expression_bodied_lambdas
Option values	true	Prefer expression bodies for lambdas
	when_on_single_line	Prefer expression bodies for lambdas when they'll be a single line
	false	Prefer block bodies for lambdas
Default option value	true

// csharp_style_expression_bodied_lambdas = true
Func<int, int> square = x => x * x;

// csharp_style_expression_bodied_lambdas = false
Func<int, int> square = x => { return x * x; };

Suppress a warning

If you want to suppress only a single violation, add preprocessor directives to your source file to disable and then re-enable the rule.

#pragma warning disable IDE0053
// The code that's violating the rule is on this line.
#pragma warning restore IDE0053

To disable the rule for a file, folder, or project, set its severity to none in the configuration file.

[*.{cs,vb}]
dotnet_diagnostic.IDE0053.severity = none

To disable all of the code-style rules, set the severity for the category Style to none in the configuration file.

[*.{cs,vb}]
dotnet_analyzer_diagnostic.category-Style.severity = none

For more information, see How to suppress code analysis warnings.

See also

• Expression-bodied members
• Code style language rules
• Code style rules reference