if语句的一般形式如下所示：if condition_1: statement_block_1elif condition_2: statement_block_2else: statement_block_3 如果 "condition_1" 为 True 将执行 "statement_block_1" 块语句 如果 "condition_1" 为False，将判断 "condition_2"如果"condition_2" 为 True 将执行 "statement_block_2...
While the match-case statement is a powerful tool, its impact on the performance of Python code, particularly in large-scale applications, should be considered. In scenarios with a large number of cases, or complex pattern matching, performance can potentially be impacted. Profiling and testing yo...
In this article, there is much emphasis on the switch case statement because there are many factors that clarify why the switch case statement has the upper hand in comparison to the if-else statement. The factors are: In comparison with the if-else ladder, a switch statement works much fas...
Structural pattern matching has been added in the form of a match statement and case statements of patterns with associated actions. Patterns consist of sequences, mappings, primitive data types as well as class instances. Pattern matching enables programs to extract information from complex data type...
while<condition>:<statement>else:<statement> 执行流程如下图所示: 条件表达式< condition >如果为真时,则循环体重复执行,直到条件判断为假,循环体终止,如果第一次判断条件就为假,则直接跳出循环执行else语句,注意else语句可以省略,同时冒号(:)开始进入循环体,缩进区分语句块。条件语句condition包括布尔表达式(True、...
statement_block_1elifcondition_2: ## 该分支可选,可以0个或多个 statement_block_2else:## 该分支可选statement_block_3 if 语句包含零个或多个elif子句,及可选的else子句。关键字 'elif' 是 'else if' 的缩写,适用于避免过多的缩进。可以把if...elif...elif... 序列看作是其他语言中switch或case语...
The Python programming language does not have a built in switch/case control structure as found in many other high level programming languages. It is thought by some that this is a deficiency in the language, and the control structure should be added. This paper demonstrates that not only is...
python if condition_1: statement_block_1 elif condition_2: statement_block_2 else: statement_block_3 如果"condition_1" 为 True 将执行 "statement_block_1" 块语句 如果"condition_1" 为False,将判断 "condition_2" 如果"condition_2" 为 True 将执行 "statement_block_2" 块语句 如果"condition_2...
classPythonSwitchStatement:defswitch(self,month): default="Invalidmonth"returngetattr(self,'case_'+str(month),lambda:default)()defcase_1(self):return"January"defcase_2(self):return"February"defcase_3(self):return"March"defcase_4(self):return"April"defcase_5(self):return"May"defcase_6(self...
statement(s); } “` 在switch语句中,expression是一个常量表达式,必须是一个整型或枚举类型。在一个switch中可以有任意数量的case语句。每个case后跟一个要比较的值和一个冒号。case的constant-expression必须与switch中的变量具有相同的数据类型,且必须是一个常量或字面量。当被测试的变量等于case中的常量时,case后...