逻辑（二进制）运算符Logical (binary) operators
支持在 bool 类型的两个值之间使用以下逻辑运算符：The following logical operators are supported between two values of the bool type:
备注
这些逻辑运算符有时称为布尔运算符，有时称为二元运算符。These logical operators are sometimes referred-to as Boolean operators, and sometimes as binary operators. 这些名称都是同义词。The names are all synonyms.
| 操作员名称Operator name | 语法Syntax | 含义Meaning |
|---|---|---|
| 相等Equality | == |
如果两个操作数均非 null 且彼此相等，则生成 true。Yields true if both operands are non-null and equal to each other. 否则为 false。Otherwise, false. |
| 不相等Inequality | != |
如果两个操作数不相等或至少有一个为 null，则生成 true。Yields true if either one (or both) of the operands are null, or they are not equal to each other. 否则为 true。Otherwise, true. |
| 逻辑与Logical and | and |
如果两个操作数都为 true，则生成 true。Yields true if both operands are true. |
| 逻辑或Logical or | or |
如果其中一个操作数是 true，则无论其他操作数如何，都将生成 true。Yields true if one of the operands is true, regardless of the other operand. |
备注
考虑到布尔 null 值 bool(null) 的行为，我们可以说：两个布尔 null 值既不相等也不不相等（换句话说，bool(null) == bool(null) 和 bool(null) != bool(null) 都生成值 false）。Due to the behavior of the Boolean null value bool(null), two Boolean null values are neither equal nor non-equal (in other words, bool(null) == bool(null) and bool(null) != bool(null) both yield the value false).
另一方面，and/or 将 null 值视为等效于 false，因此 bool(null) or true 为 true，bool(null) and true 为 false。On the other hand, and/or treat the null value as equivalent to false, so bool(null) or true is true, and bool(null) and true is false.