switch中可以有任意数量的case语句。 case语句只能包含常量,它不能是变量或表达式。 variable_expression和常量表达式的数据类型必须匹配。 除非你在每个代码块之后放置break语句,否则执行会流入下一个break块。 case表达式必须是唯一的。 default块是可选的。流程图void main() { var grade = "A";
multiline string consistiongofmultiple lines""";print(multilineString); 5.使用r前缀创建“原始raw”字符串 代码语言:javascript 复制 String s4="adbchi\ndfafa";print(s4);String s5=r"adbchi\ndfafa";print(s5); 输出的结果 代码语言:javascript 复制 I/flutter(17682):adbchiI/flutter(17682):dfafaI/...
Note: I originally raised this issue in dart-code, and was directed to raise it here. There's a neat code action to convert switch statements into expressions that take advantage of Dart 3's pattern matching: Unfortunately, it does not w...
switch (request_id.Value()) { IO_SERVICE_REQUEST_LIST(CASE_REQUEST); default: UNR...
The switch statement, on the other hand, is like a junction with multiple routes. Depending on the value of a variable or expression, we can choose different paths to execute. 另一方面,switch语句就像一个有多条路由的交叉点。根据变量或表达式的值,我们可以选择不同的执行路径。
6.1.5 switch case 6.1.6 assert 6.1.7 大部分使用方法都是和Java相同的 6.2 for-in 6.3 assert 7 异常 7.1 说明 7.2 Exception类型 7.3 Error类型 7.4 Dart中处理异常的方式 7.4.1 throw抛出异常 7.4.2 try-on处理特定类型的异常; 7.4.3 try-catch处理无法预料的异常 7.4.4 try-on...
switch case assert 大部分使用方法都是和Java相同的。 不同的有 for-in var colorList = ['black','red','yellow']; for(var i in colorList){ print(i); } 输出: I/flutter (31601): black I/flutter (31601): red I/flutter (31601): yellow ...
由于从github上拉的项目版本不一致,所以要更换dart sdk版本的需求,可以用flutter version命令切换到相应的Flutter版本,但Flutter从1.22版本开始不再推荐使用flutter version命令切换版本。建议使用fvm(Flutter Version Management)来管理不同的Flutter版本。 FVM是一个Flutter版本管理工具,它允许您在不同的项目之间轻松切换Flut...
The body of the switch keyword is placed inside a pair or curly brackets. In the body, we can place multiple case options. Each option is ended with the break keyword. case DateTime.sunday: print("dies Solis"); break; With the case statement, we test the value of the matching ...
switch (obj.runtimeType) { case DioException: // Here's the sample to get the failed response error code and message final res = (obj as DioException).response; logger.e('Got error : ${res.statusCode} -> ${res.statusMessage}'); break; default: break; } }); Relative API base...