String localeCompare() Method

localeCompare() compares two strings and returns:

If the string is alphabetically before the string argument, a negative number is returned.
If the strings are equal, 0 is returned.
If the string is alphabetically after the string argument, a positive number is returned.

 
<!DOCTYPE html>
<html>
<head>
    <title>Example</title>
    <script type="text/javascript">
    
        var stringValue = "A"; 
        document.writeln(stringValue.localeCompare("a")); //-32
        document.writeln(stringValue.localeCompare("A")); //0 
        document.writeln(stringValue.localeCompare("B")); //-1 
        
        function determineOrder(value) { 
            var result = stringValue.localeCompare(value); 
            if (result < 0){
                document.writeln("before"); 
            } else if (result > 0) { 
                document.writeln("after"); 
            } else { 
                document.writeln("equal"); 
            } 
        } 
        
        determineOrder("a"); 
        determineOrder("A"); 
        determineOrder("B"); 
        

       
    </script>
</head>
<body>
</body>
</html>

Click to view the demo