如果值在两个数字之间 [英] if value is between two numbers

问题描述

我希望能够测试一个值是否在数字范围内。这是我的jQuery代码......

I want to be able to test whether a value is within a number range. This is my jQuery code...

if ((year < 2099) && (year > 1990)){
    return 'good stuff';
}

在jQuery中有更简单的方法吗？例如，有这样的东西......

Is there a simpler way to do this in jQuery? For example, is there something like this...

if (1990 < year < 2099){
    return 'good stuff';
}

推荐答案

在许多语言中，第二种对于你想要的东西，将从左到右错误地评估方式。

In many languages, the second way will be evaluated from left to right incorrectly with regard to what you want.

例如，在C中， 1990<年将评估为0或1，然后变为 1< 2099 ，当然总是如此。

In C, for instance, 1990 < year will evaluate to 0 or 1, which then becomes 1 < 2099, which is always true, of course.

Javascript非常类似于C： 1990< year 返回 true 或 false ，这些布尔表达式似乎在数字上比较等于0分别为。

Javascript is a quite similar to C: 1990 < year returns true or false, and those boolean expressions seem to numerically compare equal to 0 and 1 respectively.

但是在C＃中，它甚至不会编译，给你错误：

But in C#, it won't even compile, giving you the error:

错误CS0019：运算符'<'不能应用于'bool'和'int'类型的操作数

error CS0019: Operator '<' cannot be applied to operands of type 'bool' and 'int'

你从Ruby得到了类似的错误，而Haskell告诉你，你不能在同一个中缀表达式中使用< 两次。

You get a similar error from Ruby, while Haskell tells you that you cannot use < twice in the same infix expression.

在我的脑海中，Python是我唯一能够处理之间设置的语言：

Off the top of my head, Python is the only language that I'm sure handles the "between" setup that way:

>>> year = 5
>>> 1990 < year < 2099
False
>>> year = 2000
>>> 1990 < year < 2099
True

底线是第一种方式（ x< y& y< z）始终是您最安全的选择。

The bottom line is that the first way (x < y && y < z) is always your safest bet.

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