The type ofswitchexpressionandcaseconstant-expressionmust be integral. The value of eachcaseconstant-expressionmust be unique within the statement body. Thecaseanddefaultlabels of theswitchstatement's body are
功能:将Switch 语句转换为 C# 8.0Switch 表达式。 使用时机:想要将switch语句转换为switch表达式,反之亦然。 操作原因:若仅在使用表达式,可以通过此重构轻松地实现传统switch语句的转换。 操作说明 在项目文件中将语言版本设置为预览版,因为switch表达式是新的 C# 8.0 功能。
2. Type switch statement The second type ofswitchstatement is typeswitchwhich compares types of value. Theswitchcases here contain type values for comparing with the interface values passed as a condition to the program. Syntax switch optionalStatement; TypeConditionExpression { case type1: // code...
switch ( expression ) case constant-expression : statement [default : statement] Remarks Theexpressionmust be of an integral type or of a class type for which there is an unambiguous conversion to integral type. Integral promotion is performed as described inIntegral Promotions. ...
switch statement (C language) - C 中文开发手册 根据整数参数的值执行代码。用于需要根据整数值执行许多代码分支中的一个或多个分支的情况。 句法 开关(表达式)语句 表达-整数类型的任何表达式(char,signed或unsigned integer或枚举)声明-任何陈述(通常是复合陈述)。情况:和默认值:标签允许在声明中,并打破...
The switch statement causes an unconditional jump to, into, or past the statement that is the “switch body,” depending on the value of the controlling expression, the values of the case labels, and the presence or absence of a default label. The switch body is normally a compound statemen...
The JavaScript Switch StatementUse the switch statement to select one of many blocks of code to be executed.Syntaxswitch(expression) { case n: code block break; case n: code block break; default: default code block } This is how it works:The switch expression is evaluated once. The value...
switch statement switch expression In those constructs, you can match an input expression against any of the following patterns: Declaration pattern: check the run-time type of an expression and, if a match succeeds, assign an expression result to a declared variable. Type pattern: check the run...
The switch statement can use the $_ and $switch automatic variables. For more information, see about_Automatic_Variables. Syntax A basic switch statement has the following format: Syntax Copy switch (<test-expression>) { <result1-to-be-matched> {<action>} <result2-to-be-matched> {<actio...
However, the syntax of the switch statement is much easier to read and write. Syntax switch (expression) { case constant1: // code to be executed if // expression is equal to constant1; break; case constant2: // code to be executed if // expression is equal to constant2; break; ....