检查变量是否为数字:Applescript

Question

如何检查变量是否为数字？

我正在尝试这个:

set a to 5
if a is a number
display dialog "Yes! It's a number!"
end if

我也试过这段代码:

set a to 5
if a is integer
display dialog "Yes! It's a number!"
end if

但不幸的是,它没有按预期工作.

Answer 1

set a to 5
if class of a is integer then
    display dialog "Yes! It's a number!"
end if

Answer 2

如果你使用 a 的类是整数将会失败

set a to "5"

即使变量是数字但作为文本输入，这也将起作用。

set a to "5"
try
    set a to a as number
    display dialog "Yes! It's a number!"
end try