In Jquery, I want to bind some buttons in a loop but failed?

I can alert each button’s id by doing so.

$(function () {
  bind_button();
});
function bind_button() {
  var len = $(".btn-sm").length;
  for(var i = 0; i < len; i ++ ){
    alert($(".btn-sm")[i].id);
  }
}

But when I want to bind the button with its id…

$(function () {
  bind_button();
});
function bind_button() {
  var len = $(".btn-sm").length;
  for(var i = 0; i < len; i ++ ){
    $(".btn-sm")[i].click(function (){
      alert($(".btn-sm")[i].id);
    });
  }
}

When I click the button, no alert appears.

Anyone knows why? And anyone knows how can I bind successfully?

>Solution :

If you want to print only the id of the clicked button just do something like

function bind_button() {
   $(".btn-sm").click(function(){
      alert(this.id);
   });
}