#CONVERT STRING TO LONG ERROR HOW TO#

Generally one of the fastest options, behaves like the + unary operator, so it does not perform conversion to an integer if the number is a float. Similar to the + unary operator, but returns the integer part, is to use Math.floor(): Math. See how it returns NaN in the first example, which is the correct behavior: it’s not a number. Its parseInt() sibling, it only takes one argument – the string to convert: parseFloat ( '10,000' ) //10 ❌ parseFloat ( '10.00' ) //10 ✅ (considered decimals, cut) parseFloat ( '10.000' ) //10 ✅ (considered decimals, cut) parseFloat ( '10.20' ) //10.2 ✅ (considered decimals) parseFloat ( '10.81' ) //10.81 ✅ (considered decimals) parseFloat ( '10000' ) //10000 ✅ Use + std::stol(): This function converts the string, provided as an argument in the function call, to long int. If you want to retain the decimal part and not just get the integer part, use parseFloat(). You should use Long.valueOf() method to parse String, if you need a Long object and use parseLong().

#CONVERT STRING TO LONG ERROR HOW TO#

ParseInt() tries to get a number from a string that does not only contain a number: parseInt ( '10 lions', 10 ) //10īut if the string does not start with a number, you’ll get NaN (Not a Number): parseInt ( 'I'm 10', 10 ) //NaNĪlso, just like Number it’s not reliable with separators between the digits: parseInt ( '10,000', 10 ) //10 ❌ parseInt ( '10.00', 10 ) //10 ✅ (considered decimals, cut) parseInt ( '10.000', 10 ) //10 ✅ (considered decimals, cut) parseInt ( '10.20', 10 ) //10 ✅ (considered decimals, cut) parseInt ( '10.81', 10 ) //10 ✅ (considered decimals, cut) parseInt ( '10000', 10 ) //10000 ✅ Thats all about how to convert String to long in Java. Other solutions Use parseInt() and parseFloat()Īnother good solution for integers is to call the parseInt() function: const count = parseInt ( '1234', 10 ) //1234ĭon’t forget the second parameter, which is the radix, always 10 for decimal numbers, or the conversion might try to guess the radix and give unexpected results. In the case you need to parse a string with decimal separators, use Intl.NumberFormat instead. If we use the constructor ( new Number('1234')) it returns us a Number object instead of a number value, so pay attention. Number is a wrapper object that can perform many operations. The best one in my opinion is to use the Number object, in a non-constructor context (without the new keyword): const count = Number ( '1234' ) //1234 JavaScript provides various ways to convert a string value into a number.

Learn how to convert a string to a number using JavaScript

Convert string to long error