convert string to number node.js

Question

I'm trying to convert req.params to Number because that is what I defined in my schema for year param.

I have tried

req.params.year = parseInt( req.params.year, 10 );   

and

Number( req.params.year); 

and

1*req.params.year; 

but non of them works. Do I need to install something?

Answer 1

You do not have to install something.

parseInt(req.params.year, 10); 

should work properly.

console.log(typeof parseInt(req.params.year)); // returns 'number' 

What is your output, if you use parseInt? is it still a string?

Answer 2

Using parseInt() is a bad idea mainly because it never fails. Also because some results can be unexpected, like in the case of INFINITY.
Below is the function for handling unexpected behaviour.

function cleanInt(x) {     x = Number(x);     return x >= 0 ? Math.floor(x) : Math.ceil(x); } 

See results of below test cases.

console.log("CleanInt: ", cleanInt('xyz'), " ParseInt: ", parseInt('xyz')); console.log("CleanInt: ", cleanInt('123abc'), " ParseInt: ", parseInt('123abc')); console.log("CleanInt: ", cleanInt('234'), " ParseInt: ", parseInt('234')); console.log("CleanInt: ", cleanInt('-679'), " ParseInt: ", parseInt('-679')); console.log("CleanInt: ", cleanInt('897.0998'), " ParseInt: ", parseInt('897.0998')); console.log("CleanInt: ", cleanInt('Infinity'), " ParseInt: ", parseInt('Infinity')); 

result:

CleanInt:  NaN  ParseInt:  NaN CleanInt:  NaN  ParseInt:  123 CleanInt:  234  ParseInt:  234 CleanInt:  -679  ParseInt:  -679 CleanInt:  897  ParseInt:  897 CleanInt:  Infinity  ParseInt:  NaN