If we are dealing with smaller number then we can leverage bit-wise operators such as bit-wise negation (
~). The reason we can only use this solution for smaller numbers is because bit-wise operations can only be executed on a number in the range of
231 - 1. If the number is outside of that range it will be converted to a number within that range (eg.
There is actually a function that will convert strings into numbers called
parseInt(). We can use this function and specify the base to ensure that numbers starting with
0 will not be parsed as octals (eg.
8 in older versions of ECMAScript).
We can also use the equivalent function to
parseInt() for floats which is
parseFloat(). After that we can use
Number.prototype.toFixed() to make the number a string representation of the truncated number. Finally we can prefix this expression with a plus sign (
+) to convert the string to a number again.
We can use the newer
Math.trunc() function which should in theory just do what we want 😆 .
Below are the results of using your browser to test out each solution:
If you have looked through the results above on a modern browser (one implementing
Math.trunc()) you’ll notice that for all of our test cases, it is the only solution that works for them all. Therefore, if you are looking to convert floating-point numbers to integers or strings to integers, the most convenient and straightforward way may in fact be ES6’s new
Math.trunc() function. Let me know what you think and as always, happy coding! 😎