string method to convert string to number javascript

If nothing is provided by default 10 is used.

radix an optional integer between the range of 2 and 36 that represents the root or the base of the numerical system.

The function expects the value to be a string if it not a string than it is automatically converted into string using the toString() method

string : The value of string that needs to be parsed or converted into a number.

Traditional methods to convert String to Number in JavaScript Using the = operator to compare a String and a Number, it is an example of implicit type conversion This is called as implicit type conversion as the developer is not explicitly type converting the value.

Implicit Type Conversion: JavaScript programming language also does type conversion automatically based on the context of the operation.

Example in JavaScript using the Number() function It is called as explicit type conversion.

Explicit Type conversion also called as type casting: When a developer intentionally converts one type into another using functions or contructs provided by the programming language for this purpose.

This process is an essential part of writing code in JS because JavsaScript is a loosely typed language where var do not have a fixed type and can be assigned and re-assigned any type Categories of Type Conversion in JS It is up to the programmer to decide which one they prefer, choosing performance over readability or a balance between the two.Type conversion in JavaScript, also called as type casting is a process of converting a value of one type (String) to another type (Number). There are many valid ways of manipulating data. Instantiating a primitive data type with the String or Number class wrapper brings performance and memory issues.

When using primitive data the object methods should not be used to create them.

Number to String let numToStr = new String( 2) // String Using String and Number ObjectsĪnother way of transforming a String to number or a number to String is creating a new String or Number object with the new keyword. The previous two approaches work simply due to the fact that JavaScript tries to assimilate the data-types used in a statement such as addition or multiplication. This approach is arguably the fastest one: let str = '100' While concise and effective, this isn't a very well-known feature of JavaScript, so it's not advised to use since it may make your code not as easy to understand. Unary OperatorĪs with Concatenating an Empty String, there is also a workaround that has better performance but lacks readability. Keep in mind that if you're needing to parse floats then both Math.floor and Math.ceil are probably not good options since they'll always convert the strings to the nearest integer equivalent. Math.ceil(str) // 100 Math.ceil(fltStr) // 101 Math.ceil(nanStr) // NaN The method can accept Strings, also making it a way to convert a String to a number: let str = '100' Very similar to the previous method, Though, this time it returns the nearest integer rounded up. Math.floor(str) // 100 Math.floor(fltStr) // 99 Math.floor(nanStr) // NaN Math.ceil() Surprisingly, this method can also accept Strings, making it yet a way to convert a String to an integer. ParseFloat(str) // 353 parseFloat(fltStr) // 353.21 parseFloat(nanStr) // NaN Math.floor() ParseInt(str) // 353 parseInt(fltStr) // 353 parseInt(binStr, 2) // 111 (Binary) parseInt(nanStr) // NaN (Not a Number). 0x - If the prefix is 0x, then the radix is 16 (hexadecimal).Īlthough, we can simply add an optional argument to the method call, defining the base: let str = '353'.

0 - If the prefix is 0, then the radix is 8 (octal).No prefix - If there isn't a prefix, the radix is 10 (decimal).The base can be defined by adding prefixes to the numbers we want to parse: If a String is multiplied by the primitive number 1, the string will become a number. Unary Operator By adding a + sign before a String, it will be converted into a number if it follows the right format.Math.ceil() can be used to round an integer or floating point number.It returns the nearest integer rounded down. Math.floor() is used to round an integer or floating point number.parseFloat() takes a String as an argument, and returns the Float point number equivalent. parseInt() takes a String as a first argument, and a base to which that String will be converted to. These are parseInt(), parseFloat(), Math.floor(), Math.ceil(), Unary Operator / Multiply by 1. Converting String to NumberĪs with the previous shown methods, JavaScript also provides functions to easily transform a String to a primitive number.

The same goes for the other way around, converting a String to a number. Converting a Number to a String is a common and simple operation. Managing data is one of the fundamental concepts of programming.

String method to convert string to number javascript