var str= "123abc";
alert (typeof (strPP)); / / number
alert (str); / / NaN / / Why is this equal to NaN? what exactly does the above strPP do? it is different from str+1
var str= "123abc";
alert (typeof (strPP)); / / number
alert (str); / / NaN / / Why is this equal to NaN? what exactly does the above strPP do? it is different from str+1
str+1 returns the string "str1"
strPP first executes Number (str), and the result is NAN. And then do the + 1 operation. It is important to note that NAN is also of type number.
so if str= "123", strPP return value (Number ("123") is 123, strvalue is 124.
I'll talk about the execution process
var str= "123abc";
alert (typeof (strPP)); / / number
alert (str); / / NaN / / Why is this equal to NaN? what exactly does the above strPP do is different from str+1alert (typeof (strPP));
execute as follows:
the second case
str+1 is string concatenation. You should know the rest.
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