JavaScript Try Parse int

JavaScript provides isNaN
, which returns a bool whether the value is an int or not. But this functionality can be wrapped into a handy function which will actually return a Number value of an object, given the specified radix. If the value is not an int, it will return a default value.

inputs are as follows:

val: the object to try to parse as an int

default_val: the value to return if this is not an int

radix: the base of the number to return (ex: 2 for binary, 10 for base10 which we are accustomed to counting in)

var int_try_parse = function(val, default_val, radix)
{
 try
 {
 radix = radix || 10;
 default_val = default_val || 0;

 //validate this object is not null
 if (val != null)
 {
 //convert to string
 var that = JSON.stringify(val);
 if (that.length > 0)
 {
 //check to see the string is not NaN, if not parse
 if (!isNaN(that)) 
 return parseInt(that, radix);
 }
 }
 }
 catch (err)
 {
 console.log(err); 
 }
 //this is not a number
 return default_val;
}

some test cases:

Binary

int_try_parse(1010, 0, 2)
=>10


int_try_parse(10, 0, 2)
=>2

Base 10

int_try_parse(1010, 0, 10)
=>1010

int_try_parse(10, 0, 10)
=>10

invalid objects

int_try_parse([1010], 0, 10)
=>0

int_try_parse({val:1010}, 0, 10)
=>0

int_try_parse({val:1010}, -50, 10)
=>-50

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