Categories

jQuery.isFunction()

Categories: Utilities

jQuery.isFunction( obj )Returns: boolean

Description: Determine if the argument passed is a Javascript function object.

  • jQuery.isFunction( obj )

    version added: 1.0

    obj   Object to test whether or not it is a function.

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.

  • Test a few parameter examples.

    HTML:
    
      <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>
      
    CSS:
    
      div { color:blue; margin:2px; font-size:14px; }
      span { color:red; }
      
    Code:
    
        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);
        });
    
  • Finds out if the parameter is a function.

    Code:
    $.isFunction(function(){});
    Results:
    true