Use switch expression (IDE0066)
Property | Value |
---|---|
Rule ID | IDE0066 |
Title | Use switch expression |
Category | Style |
Subcategory | Language rules (pattern matching preferences) |
Applicable languages | C# 8.0+ |
Introduced version | Visual Studio 2019 |
Options | csharp_style_prefer_switch_expression |
Overview
This style rule concerns the use of switch expressions, which were introduced in C# 8.0, versus switch statements.
Options
Options specify the behavior that you want the rule to enforce. For information about configuring options, see Option format.
csharp_style_prefer_switch_expression
Property | Value | Description |
---|---|---|
Option name | csharp_style_prefer_switch_expression | |
Option values | true |
Prefer to use a switch expression |
false |
Prefer to use a switch statement |
|
Default option value | true |
// csharp_style_prefer_switch_expression = true
return x switch
{
1 => 1 * 1,
2 => 2 * 2,
_ => 0,
};
// csharp_style_prefer_switch_expression = false
switch (x)
{
case 1:
return 1 * 1;
case 2:
return 2 * 2;
default:
return 0;
}
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 IDE0066
// The code that's violating the rule is on this line.
#pragma warning restore IDE0066
To disable the rule for a file, folder, or project, set its severity to none
in the configuration file.
[*.{cs,vb}]
dotnet_diagnostic.IDE0066.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.