Easy way to convert a string to a number or null?

问题

Is there a slick way to convert a string to a number or null if it cannot be represented by a number? I have been using the method below:

if _.isNaN( Number(mystring)  ) then null else Number(mystring)

Which works, but I'm curious if there is something that is shorter? Possible, or is this the most succinct way?

回答1:

If you don't care for "0", then you can use

+s||null

If you want to support "0", then I don't have better than

1/s?+s:null

回答2:

This is a small improvement to the OP's answer, and is fairly readable:

isNaN(mystring) ? null : +mystring

来源：https://stackoverflow.com/questions/21636913/easy-way-to-convert-a-string-to-a-number-or-null