This version of the code adds a boolean variable , 这个版本的代码添加了一个布尔变量
If you require a boolean variable that can also have a value of 值的布尔型变量,请使用
Nullable booleans are similar to the boolean variable type used in sql 可空布尔值类似于sql中使用的布尔变量类型。为了确保
For an example of when you might use a nullable type , consider how an ordinary boolean variable can have two values : true and false 有关可能使用可空类型的示例,请考虑普通的布尔变量如何能够具有两个值: true和false 。
For example , c treats boolean variables as single - byte values , while the common language runtime marshals them as four - byte values to match the boolean type defined by the microsoft win32 api 例如, c + +将布尔变量视为单字节值,而公共语言运行库将它们作为四字节值进行封送以匹配microsoft win32 api定义的