How to empty an array in JavaScript?

Last Updated : 01 Apr, 2019

There are many ways to empty an array in JavaScript some of them are discussed below:

Method 1: Setting to new Array: This method sets the array variable to new array of size zero, then it will work perfectly.

Example:

<!DOCTYPE html>   
<html>   
  
<head>  
    <title>  
        JavaScript to set array empty 
    </title> 
</head>  
           
<body style = "text-align:center;">   
       
    <h1 style = "color:green;" >   
        GeeksForGeeks   
    </h1>   
               
    <p id = "up"></p> 
      
    <button onclick="empty()">  
        Click to Empty 
    </button>  
      
    <p id = "down" style="color: green"></p> 
      
    <!-- Script to set size of array to zero -->
    <script>  
        var GFG_Array = [1, 2, 3, 4, 5]; 
        var up = document.getElementById("up"); 
        up.innerHTML = GFG_Array; 
        var down = document.getElementById("down"); 
        down.innerHTML = "length of GFG_Array = " 
                + GFG_Array.length; 
        function empty() { 
            GFG_Array = []; 
            down = document.getElementById("down"); 
            down.innerHTML = "length of GFG_Array = " 
                    + GFG_Array.length; 
        } 
    </script>  
</body>   
  
</html> 

Output:

Before clicking the button:
After clicking the button:

Method 2: Using length property: This method sets the length of array to zero.

Example:

<!DOCTYPE html>  
<html>  
  
<head>  
    <title>  
        Create empty array 
    </title> 
</head>  
          
<body style = "text-align:center;">  
  
    <h1 style = "color:green;" >  
        GeeksForGeeks  
    </h1>  
              
    <p id="up"></p> 
      
    <button onclick="empty()">  
        Click to Empty 
    </button>  
      
    <p id="down" style="color: green"></p> 
      
    <!-- Script to set the size of array to zero -->
    <script>  
        var GFG_Array = [1, 2, 3, 4, 5]; 
        var up = document.getElementById("up"); 
        up.innerHTML = GFG_Array; 
        var down = document.getElementById("down"); 
        down.innerHTML = "length of GFG_Array = " 
                + GFG_Array.length; 
                  
        function empty() { 
            GFG_Array.length = 0; 
            down = document.getElementById("down"); 
            down.innerHTML = "length of GFG_Array = " 
                    + GFG_Array.length; 
        } 
    </script>  
</body>  
  
</html>                     

Output:

Before clicking the button:
After clicking the button:

Method 3: Using pop method: This method pop the array element continuously and get the empty array. But this method takes more time than others and not much preferred.
Example:

<!DOCTYPE html>  
<html>  
  
<head>  
    <title>  
        Create empty array 
    </title> 
</head> 
          
<body style = "text-align:center;">  
      
    <h1 style = "color:green;" >  
        GeeksForGeeks  
    </h1>  
              
    <p id="up"></p> 
      
    <button onclick="empty()">  
        Click to Empty 
    </button>  
      
    <p id="down" style="color: green"></p> 
      
    <!-- Script to set the size of array to zero -->    
    <script>  
        var GFG_Array = [1, 2, 3, 4, 5]; 
        var up = document.getElementById("up"); 
        up.innerHTML = GFG_Array; 
        var down = document.getElementById("down"); 
        down.innerHTML = "length of GFG_Array = " 
                + GFG_Array.length; 
                  
        function empty() { 
            while(GFG_Array.length > 0) { 
                GFG_Array.pop(); 
            } 
            down = document.getElementById("down"); 
            down.innerHTML = "length of GFG_Array = " 
                    + GFG_Array.length; 
        } 
    </script>  
</body>  
  
</html>                     

Output:

Before clicking the button:
After clicking the button:

My Personal Notes

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