检查值是否在数字范围内
问题描述：
我想检查某个值是否在可接受的范围内。如果是，做某事;否则，别的。
I want to check if a value is in an accepted range. If yes, to do something; otherwise, something else.
范围是 0.001-0.009 。我知道如何使用多个 if 来检查这个，但我想知道是否有办法在单个中检查它是否声明。
The range is 0.001-0.009. I know how to use multiple if to check this, but I want to know if there is any way to check it in a single if statement.
答
你问一个关于数字比较的问题，所以正则表达式实际上与问题。您不需要多个 if 语句来执行此操作：
You're asking a question about numeric comparisons, so regular expressions really have nothing to do with the issue. You don't need "multiple if" statements to do it, either:
if (x >= 0.001 && x <= 0.009) {
// something
}
你可以自己写一个between（）函数：
You could write yourself a "between()" function:
function between(x, min, max) {
return x >= min && x <= max;
}
// ...
if (between(x, 0.001, 0.009)) {
// something
}