您是对的，这是实现此目的的方法之一.如果您的"String"变量不是字符串，它只会起作用并抛出错误.

You're right, this is one of the ways to do it. It would only not work and throw errors if your "String" variable is not a string.

我个人通常更喜欢使用类似的东西.

Personally, i usually prefer to use something like..

myString = string.lower(myString)

但实际上和做的一样

myString = myString:lower()

但是，假设myString实际上是一个字符串.

assuming that myString is actually a string, however.

"long"版本具有一个优点，如果myString是数字，则它实际上可以工作，而第二个则在这种情况下会出错.

The "long" version has one advantage, it actually works if myString is a number, while the second one errors in that case.