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In this tutorial, we will learn to check if a value is a safe integer in JavaScript. The simple definition of safe integers in JavaScript are all numbers that we can represent as IEEE-754 double precision numbers. It is the set of all numbers between -(2^53) and (2^53), and we can represent it in the standard way.
Here we have different methods to check if a number is a safe integer.
Use Number.IsSafeInteger() method
Use if-else conditional statements
In JavaScript, the isSafeInteger() method checks whether the type of a value is a number and is between -(2^53) and (2^53). We can pass different values as arguments to this method and return a Boolean value as the result. Returns true if the number is a safe integer, false otherwise.
Users can use the following syntax to use the isSafeInteger() method
let isSafe = Number.isSafeInteger(value);
value - This is the value of any variable where the user wants to check if the value is a safe integer.
In the example below, we use the Number.isSafeInteger() method to check if the value is a safe integer. We checked it for different values like boolean, string, float and integer
<html> <head> </head> <body> <h2>Check if value is safe Integer or not in JavaScript.</h2> <h4>Check if value is safe Integer or not using <i> isSafeInteger() </i> method.</h4> <div id = "output"></div> <script> var output = document.getElementById("output"); let value = 1000; let isSafe = Number.isSafeInteger(value); output.innerHTML += "1000 is safe Integer : " + isSafe + " <br/> "; output.innerHTML += "true is safe Integer : " + Number.isSafeInteger(true) + " <br/> "; output.innerHTML += "'Hello' is safe Integer : " + Number.isSafeInteger("hello") + " <br/> "; output.innerHTML += "Math.pow(2,53) is safe Integer : " + Number.isSafeInteger(Math.pow(2, 53)) + " <br/> "; output.innerHTML += "123.43 is safe Integer : " + Number.isSafeInteger(123.43) + " <br/> "; output.innerHTML += "-90 is safe Integer : " + Number.isSafeInteger(-90) + " <br/> "; </script> </body> </html>
In this method we will simply use if-else statement to check if the value is of numeric type. If the value is a number, we check if it is between -(2^53) and (2^53). This is custom logic based on the isSafeInteger() method which returns a boolean output.
The syntax for using an if-else statement to check whether a value is a safe integer is as follows.
if ( typeof value === 'number' && -Math.pow(2, 53) < value && Math.pow(2, 53) > value ) { // value is safe integer } else { // value is not safe integer }
In the following example, we simply implement the above method. We created a function called safeInteger() that checks for a safe integer based on the above method and returns a Boolean value.
<html> <head> </head> <body> <h2>Check if value is safe Integer or not in JavaScript.</h2> <h4>Check if value is safe Integer or not using <i> if-else</i> statement.</h4> <div id = "output"></div> <script> var output = document.getElementById("output"); function safeInteger(value) { if ( typeof value === 'number' && -Math.pow(2, 53) < value &&Math.pow(2, 53) > value ) { return true; } else { return false; } } output.innerHTML += " safeInteger (-90) : " + safeInteger(-90) + " <br/> "; output.innerHTML += " safeInteger (true) : " + safeInteger(true) + " <br/> "; output.innerHTML += " safeInteger ('yes') : " + safeInteger('yes') + " <br/> "; output.innerHTML += " safeInteger (123.6543) : " + safeInteger(123.6543) + " <br/> "; </script> </body> </html>
We learned two different ways to check if the value is a safe integer. In the first method, we use the built-in method; in the second method, we implement the first method from scratch.
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