括号首选项（IDE0047 和 IDE0048）

项目
04/07/2023

本文介绍了两个相关的规则：IDE0047 和 IDE0048。

属性	值
规则 ID	IDE0047
标题	删除不必要的括号
类别	Style
Subcategory	语言规则（括号首选项）
适用的语言	C# 和 Visual Basic
引入的版本	Visual Studio 2017
选项	`dotnet_style_parentheses_in_arithmetic_binary_operators`
	`dotnet_style_parentheses_in_relational_binary_operators`
	`dotnet_style_parentheses_in_other_binary_operators`
	`dotnet_style_parentheses_in_other_operators`

属性	值
规则 ID	IDE0048
标题	为清楚起见，请添加括号
类别	Style
Subcategory	语言规则（括号首选项）
适用的语言	C# 和 Visual Basic
引入的版本	Visual Studio 2017
选项	`dotnet_style_parentheses_in_arithmetic_binary_operators`
	`dotnet_style_parentheses_in_relational_binary_operators`
	`dotnet_style_parentheses_in_other_binary_operators`
	`dotnet_style_parentheses_in_other_operators`

概述

本部分中的样式规则涉及括号优先权，包括使用括号来声明算术、关系和其他二元运算符的优先级。

选项

此规则具有关联的选项，用于根据运算符的类型指定优先权：

算术二元运算符 - dotnet_style_parentheses_in_arithmetic_binary_operators
关系二元运算符 - dotnet_style_parentheses_in_relational_binary_operators
其他二元运算符 - dotnet_style_parentheses_in_other_binary_operators
其他运算符 - dotnet_style_parentheses_in_other_operators

若要了解如何配置选项，请参阅选项格式。

dotnet_style_parentheses_in_arithmetic_binary_operators

属性	值	说明
选项名称	dotnet_style_parentheses_in_arithmetic_binary_operators
选项值	`always_for_clarity`	优先使用括号来声明算术运算符优先级
	`never_if_unnecessary`	算术运算符的优先级显而易见时，最好不要使用括号
默认选项值	`always_for_clarity`

算术二元运算符包括：*、/、%、+、-、<<、>>、&、^ 和 |。

// dotnet_style_parentheses_in_arithmetic_binary_operators = always_for_clarity
var v = a + (b * c);

// dotnet_style_parentheses_in_arithmetic_binary_operators = never_if_unnecessary
var v = a + b * c;

' dotnet_style_parentheses_in_arithmetic_binary_operators = always_for_clarity
Dim v = a + (b * c)

' dotnet_style_parentheses_in_arithmetic_binary_operators = never_if_unnecessary
Dim v = a + b * c

dotnet_style_parentheses_in_relational_binary_operators

属性	值	说明
选项名称	dotnet_style_parentheses_in_relational_binary_operators
选项值	`always_for_clarity`	优先使用括号来声明关系运算符优先级
	`never_if_unnecessary`	关系运算符的优先级显而易见时，最好不要使用括号
默认选项值	`always_for_clarity`

关系二元运算符包括：>、<、<=、>=、is、as、== 和 !=。

// dotnet_style_parentheses_in_relational_binary_operators = always_for_clarity
var v = (a < b) == (c > d);

// dotnet_style_parentheses_in_relational_binary_operators = never_if_unnecessary
var v = a < b == c > d;

' dotnet_style_parentheses_in_relational_binary_operators = always_for_clarity
Dim v = (a < b) = (c > d)

' dotnet_style_parentheses_in_relational_binary_operators = never_if_unnecessary
Dim v = a < b = c > d

dotnet_style_parentheses_in_other_binary_operators

属性	值	说明
选项名称	dotnet_style_parentheses_in_other_binary_operators
选项值	`always_for_clarity`	优先使用括号来声明其他二元运算符优先级
	`never_if_unnecessary`	其他二元运算符的优先级显而易见时，最好不要使用括号
默认选项值	`always_for_clarity`

其他二元运算符包括：&&、|| 和 ??。

// dotnet_style_parentheses_in_other_binary_operators = always_for_clarity
var v = a || (b && c);

// dotnet_style_parentheses_in_other_binary_operators = never_if_unnecessary
var v = a || b && c;

' dotnet_style_parentheses_in_other_binary_operators = always_for_clarity
Dim v = a OrElse (b AndAlso c)

' dotnet_style_parentheses_in_other_binary_operators = never_if_unnecessary
Dim v = a OrElse b AndAlso c

dotnet_style_parentheses_in_other_operators

属性	值	说明
选项名称	dotnet_style_parentheses_in_other_operators
选项值	`always_for_clarity`	优先使用括号来声明其他运算符优先级
	`never_if_unnecessary`	其他运算符的优先级显而易见时，最好不要使用括号
默认选项值	`never_if_unnecessary`

此选项适用于除以下运算符以外的运算符：

*, /, %, +, -, <<, >>, &, ^, |>, <, <=, >=, is, as, ==, !=&&, ||, ??

// dotnet_style_parentheses_in_other_operators = always_for_clarity
var v = (a.b).Length;

// dotnet_style_parentheses_in_other_operators = never_if_unnecessary
var v = a.b.Length;

' dotnet_style_parentheses_in_other_operators = always_for_clarity
Dim v = (a.b).Length

' dotnet_style_parentheses_in_other_operators = never_if_unnecessary
Dim v = a.b.Length

抑制警告

如果只想抑制单个冲突，请将预处理器指令添加到源文件以禁用该规则，然后重新启用该规则。

#pragma warning disable IDE0047 // Or IDE0048
// The code that's violating the rule is on this line.
#pragma warning restore IDE0047 // Or IDE0048

若要对文件、文件夹或项目禁用该规则，请在配置文件中将其严重性设置为 none。

[*.{cs,vb}]
dotnet_diagnostic.IDE0047.severity = none
dotnet_diagnostic.IDE0048.severity = none

若要禁用所有代码样式规则，请在配置文件中将类别 Style 的严重性设置为 none。

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

有关详细信息，请参阅如何禁止显示代码分析警告。