逗号运算符返回参数列表中的第一个值而不是第二个值？
MDN claims that:
The comma operator evaluates both of its operands (from left to right)
and returns the value of the second operand.
However, when I tried running <script> alert(1, 2); </script>, it shows a "1" instead of a "2".
Am I misunderstanding something?
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在函数调用的上下文中，逗号用于将参数彼此分隔。因此，您要做的就是将第二个参数传递给
alert()，该参数会被默默地忽略。你想要的可以这样实现：
额外的括号本身形成一个参数；在它们内部，您可以使用逗号作为运算符。
In the context of a function call, the comma is used to separate parameters from each other. So what you're doing is passing a second parameter to
alert()which gets silently ignored.What you want is possible this way:
The extra brackets form a parameter on their own; inside them you can use the comma as an operator.
逗号
(,)也是一个参数分隔符。请改用
alert((1,2))。Comma
(,)is also a parameter separator.Use
alert((1,2))instead.当您这样使用它时，逗号不是一个运算符，它是调用
alert方法时参数之间的分隔符。如果您将它们放在括号中以使其成为一个表达式，它将显示
2：When you use it like that, the comma is not an operator, it's a separator between the parameters in the call to the
alertmethod.If you put parentheses around them so that it's an expression, it will show you
2: