Extract a number from a string using JavaScript

The number from a string in javascript can be extracted into an array of numbers by using the match method. This function takes a regular expression as an argument and extracts the number from the string. Regular expression for extracting a number is (/(\d+)/).

Example 1: This example uses match() function to extract number from string.

<!DOCTYPE html> 
<html> 
<head> 
    <title> 
        Extract number from string 
    </title> 
</head> 
  
<body > 
    <div align="center" style="background-color: green;"> 
          
        <h1>GeeksforGeeks</h1> 
          
        <p>String is "jhkj7682834"</p> 
          
        <p id="GFG">  
            Click the button to extract number 
        </p> 
          
        <input type="button" value="click " onclick="myGeeks()"> 
    </div> 
      
    <script> 
        function myGeeks() { 
            var str = "jhkj7682834"; 
            var matches = str.match(/(\d+)/); 
              
            if (matches) { 
                document.getElementById('GFG').innerHTML 
                        = matches[0]; 
            } 
        } 
    </script> 
</body> 
</html>                                 

Output:

Before Clicking the button:
After Clicking the button:

Example 2: This example uses match() function to extract number from string.

<!DOCTYPE html> 
<html> 
<head> 
    <title> 
        Extract number from string 
    </title> 
</head> 
  
<body> 
    <div align="center" style="background-color: green;"> 
          
        <h1>GeeksforGeeks</h1> 
          
        <p>String is "foo35bar5jhkj88"</p> 
          
        <h3> 
            The string contains 3 numbers. So the numbers 
            are stored in an array and print together 
        </h3> 
          
        <p id="GFG"> 
            Click the button to extract number 
        </p><br> 
          
        <h3 id="Geeks"></h3> 
          
        <input type="button" value="Click Here!" onclick="myGeeks()"> 
    </div> 
      
    <script> 
        function myGeeks() { 
            var str = "foo35bar5jhkj88"; 
            matches = str.match(/\d+/g); 
            var i=0 
          
            document.getElementById('GFG').innerHTML 
                = matches[0] + matches[1] + matches[2]; 
              
            document.getElementById("Geeks").innerHTML 
                = "Where 35 is the first, 5 is the second" 
                + " and 88 is the third number" 
    } 
    </script> 
</body> 
</html>                     

Output:

Before Clicking the button:
After Clicking the button:

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