Prototype - blank() Method

This method checks if the string is 'blank', meaning either empty or containing only whitespace.

Syntax

string.blank();

Return Value

Returns a boolean value. Either true if string is empty or false if string is not empty.

Example

<html>
   <head>
      <title>Prototype examples</title>
      <script type = "text/javascript" src = "/javascript/prototype.js"></script>
      
      <script>
         function showResult() {
            var str = '';
            alert("''.blank() : " + str.blank() );
            str = '  ';
            alert("'  '.blank() : " + str.blank() );
            str = 'a';
            alert("a.blank() : " + str.blank() );
         }
      </script>
   </head>

   <body>
      <p>Click the button to see the result.</p>
      <br />
      <br />
      <input type = "button" value = "Result" onclick = "showResult();"/>
   </body>
</html>

Output

prototype_string_processing.htm