1 <script type="text/javascript"> 2         var  getString=function(fileName){ 3                 return fileName.split(".").pop(); 4         } 5         //例1 6         var fileName1 = "photo.jpg"; 7         var getString1 = getString(fileName1);    // 获取值 jpg 8         alert(getString1); 9 10         //例211         var fileName2 = "main.js";12         var getString2 = getString(fileName2);   // 获取值 js13         alert(getString2);14     </script>