ActionScript：我应该始终使用严格相等（“===”）吗？
我想知道在进行相等性检查时是否应该始终使用“===”（严格相等）...是否有任何例子说明何时最好使用“==”（非严格平等）？特别是，应该：
if (param1 == null || param1.length == 0)
为
if (param1 === null || param1.length === 0)代码>？
那么像字符串这样的东西呢？ param1 ==“这是一个字符串。”
I'm wondering if I should always use "===" (strict equality) when doing equality checks... Is there any example of when it is preferable to use "==" (non-strict equality)? In particular, should:
if (param1 == null || param1.length == 0)
be
if (param1 === null || param1.length === 0)?
What about with things like strings? param1 == "This is a String."
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应使用的运算符取决于您的需要。
“==”检查两个值在转换为相同数据类型后是否相等（如果可能）。因此，“5”== 5 为真，因为字符串“5”被转换为数字，然后进行检查，显然 5 实际上等于 5
。“===”检查两个值是否类型相同且相等。因此，“5” === 5 将计算为 false，因为 1 是字符串，1 是数字。
在用途选择方面，归结为期望。如果您希望比较的两个值具有相同类型，那么您应该使用“===”。但是，如果它们可以是不同的类型，并且您希望比较自动执行转换（例如，将字符串 5 与数字 5 进行比较），则可以使用“==”。
在您的示例中，所有这些都应该可以使用“==”运算符，但为了增加类型安全性，您当然可以使用“===”运算符。例如，我倾向于专门检查空值。
希望这有帮助。
The operator that should be used depends on your needs.
The "==" checks if two values are equal after they've been converted to the same datatype (if possible.) So, "5" == 5 would be true, because the string "5" is converted to a number, and then the check is made, and obviously 5 does in fact equal 5.
The "===" checks if two values are the same type AND equal. So, "5" === 5 would evaluate to false because one is a string and one is a number.
In terms of choice of use, it comes down to expectations. If you expect the two values your comparing to be of the same type, then you should use "===". However, if they can be of different types and and you want the comparison to perform the conversion automatically (e.g., comparing a string 5 to a number 5), then you can use "==".
In the case of your examples, all of them should be fine with the "==" operator, but for added type safety, you certainly can use the "===" operator. I tend to specifically check for nulls, for instance.
Hope this helps.
我实际上不太了解 ActionScript，但我相信它符合 EMCAScript，这意味着我的 JavaScript 知识是相关的。
在 JavaScript 中，如果您愿意接受显式类型（这意味着永远不要执行
"something" + 5，请始终在类型中显式显示，例如"something" + String(5)"something" + String(5) code>），如果您采用这种方法，实际上永远不会出现 == 优于 === 的情况。I don't actually know much about ActionScript, but I believe it's EMCAScript compliant which means my JavaScript knowledge would be relevant.
In JavaScript, if you're willing to embrace explicit typing (this means never do
"something" + 5, always be explicit in your types e.g."something" + String(5)), if you embrace that approach there's actually never an instance where == is preferred to ===.