如果第一个表达式为假，则编译器是否会继续计算所有表达式都必须为真的表达式？
我确信这个问题之前可能已经得到解答，所以我很抱歉，但我无法找到正确的搜索词来找到答案。
给出以下代码示例，db.GetRecords().Any() 是否被执行？
string s = "Z";
bool x = s.IndexOfAny(new[] { 'A', 'B' }) > 0 &&
db.GetRecords().Any();
I'm sure this question has probably been answered before, so I apologize, but I wasn't able to find the proper search terms to find the answer.
Given the following code example, does db.GetRecords().Any() get executed?
string s = "Z";
bool x = s.IndexOfAny(new[] { 'A', 'B' }) > 0 &&
db.GetRecords().Any();
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否。
&&和||均由 短路评估。这意味着a &&如果返回 true，并且在这两种情况下都不会计算a为 false 并且a || b返回 false如果a为 true，bb。如果由于某种原因您不想进行短路计算，您可以使用按位运算符
&和|。No. Both
&&and||are evaluated by short-circuit evaluation. This means thata && breturns false ifais false anda || breturns true ifais true and it will not evaluatebin either of these cases.If for some reason you do not want short-circuit evaluation you can use the bitwise operators
&and|.不会。
&&运算符会短路（这意味着在表达式的任何部分计算结果为 false 后，它会停止计算表达式）。||运算符也会短路，但在表达式的任何部分计算结果为 true 后停止计算。No. The
&&operator short-circuits (which means it stops evaluating the expression after any part of the expression evaluates to false).The
||operator also short-circuits but stops evaluating after any part of the expression evaluates to true.不，C# 使用短路和。所以答案是不。
如果您需要同时评估两者，请仅使用一个与号 & 来使用 NON-SHORT-CIRCUIT 运算符。
请注意单个&。
No, C# use short circuit and. So the answer is no.
If you need to evaluate both, use NON-SHORT-CIRCUIT operator by using just one ampersand &.
Please note the single &.
不
No
我说的是 C# 逻辑 AND (
&&)，第二个表达式为假，因为它们都需要为真才能使表达式为真，所以编译器立即停止计算。与逻辑与相反，逻辑或 (
||) 只需要所有表达式中只有一个表达式为真，整个表达式就为真。因此，||运算符不会使false求值短路，而是使编译器对 true 求值短路。现在，这是 C# 编译器的行为，但这并不意味着每个编译器都这样做，就像在 VB.NET 中一样，您有两个逻辑与运算符 (
和，AndAlso），以及两个逻辑或运算符（Or、OrElse）。And运算符用于按位和逻辑连接，当第一个表达式返回 false 并计算另一个表达式时，它不会短路，而AndAlso会短路当第一个逻辑表达式为假时求值。这与Or和OrElse相同，其中Or不会短路，而OrElse会短路。简而言之，我想说这取决于您正在使用的编译器。至于C#，它确实短路了。
I say that for a C# logic-AND (
&&), the second that an expression is false, since they all need to be true for the expression to be true, the compiler stops evaluating immediately.Contrarely to a logic-AND, the logic-OR (
||) only requires only one expression among all to be true, for the whole expression to be true. So, instead of short-circuiting over afalseevaluation, the||operator causes the compiler to short-circuit over a true evaluation.Now, that is the behaviour of the C# compiler, but it doesn't mean every compiler bahves that way, as in VB.NET, you have two logic-AND operators (
And,AndAlso), and two logic-OR operators (Or,OrElse). TheAndoperator, used for both bitwise and logic conjunctions, does not short-circuit when the first expression returns false and evaluate the other anyway, whileAndAlsowill short-circuit the evaluation when the first logical expression is false. That is the same withOrandOrElse, whereOrdoesn't short-circuit, andOrElsedoes.In short, I would say that this depends on the compiler you're working with. As for C#, it does short-circuit.
它是短路的，允许您执行以下操作：
如果两个操作都被评估，则有可能引用空对象，这将是运行时异常。
It is shortcircuiting and allows you to do things like this:
if both operations were evaluated, there would be a possibility of referencing a null object, which would be a runtime exception.