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Utilities/jQuery.isFunction

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jQuery.isFunction( obj )

Determine if the parameter passed is a Javascript function object.

Note: As of jQuery 1.3, functions provided by the browser like 'alert', and DOM element methods like 'getAttribute', are not guaranteed to be detected as functions in browsers such as Internet Explorer.

Arguments:
objObject
Object to test whether or not it is a function.
Examples:

Test a few parameter examples.

    function stub() {
    }
    var objs = [
          function () {},
          { x:15, y:20 },
          null,
          stub,
          "function"
        ];

    jQuery.each(objs, function (i) {
      var isFunc = jQuery.isFunction(objs[i]);
      $("span").eq(i).text(isFunc);
    });

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" 
                    "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
  <script src="http://code.jquery.com/jquery-latest.js"></script>
  
  <script>
  $(document).ready(function(){
    
    function stub() {
    }
    var objs = [
          function () {},
          { x:15, y:20 },
          null,
          stub,
          "function"
        ];

    jQuery.each(objs, function (i) {
      var isFunc = jQuery.isFunction(objs[i]);
      $("span").eq(i).text(isFunc);
    });

  });
  </script>
  <style>
  div { color:blue; margin:2px; font-size:14px; }
  span { color:red; }
  </style>
</head>
<body>
  
  <div>jQuery.isFunction(objs[0]) = <span></span></div>
  <div>jQuery.isFunction(objs[1]) = <span></span></div>
  <div>jQuery.isFunction(objs[2]) = <span></span></div>
  <div>jQuery.isFunction(objs[3]) = <span></span></div>
  <div>jQuery.isFunction(objs[4]) = <span></span></div>
  
</body>
</html>

Finds out if the parameter is a funcion.

$.isFunction(function(){});

true

NameType