How to check if a value is a safe integer in JavaScript?-HTML Tutorial-php.cn

How to check if a value is a safe integer in JavaScript?

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Release： 2023-09-15 18:25:02

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How to check if a value is a safe integer in JavaScript?

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

Use Number.isSafeInteger() method

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.

grammar

Users can use the following syntax to use the isSafeInteger() method

let isSafe = Number.isSafeInteger(value);

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parameter

value - This is the value of any variable where the user wants to check if the value is a safe integer.

Example

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>

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Use if-else conditional statements

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.

grammar

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
   }

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Example

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>

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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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