title: How to add callback function in jQuery?
body: <pre><code>function $(id) {
      if (id) {
          if (window === this) {
              return new $(id);
          }
  
          this.e = document.getElementById(id);
          return this;
      } else {
          return about;
      }
  }
  
  $.prototype = {
      click: function () {
          this.e.onclick = function () {
              alert("hi..");
          }
      }
  };
  </code></pre>
  
  <p>when I excute this code : </p>
  
  <pre><code>$("skg").click2();
  </code></pre>
  
  <p>it return alert msg.</p>
  
  <p>But I want to add a callback function like this : </p>
  
  <pre><code>$("skg").click(function(){
      alert("hi SKG");
  });
  </code></pre>
  
  <p>How to do this?</p>