JQuery .on（）方法，具有一个选择器的多个事件处理程序

Question

Trying to figure out how to use the Jquery .on() method with a specific selector that has multiple events associated with it. I was previously using the .live() method, but not quite sure how to accomplish the same feat with .on(). Please see my code below:

$("table.planning_grid td").live({
  mouseenter:function(){
     $(this).parent("tr").find("a.delete").show();
  },
  mouseleave:function(){
     $(this).parent("tr").find("a.delete").hide();        
  },
  click:function(){
    //do something else.
  }
});

I know I can assign the multiple events by calling:

 $("table.planning_grid td").on({
    mouseenter:function(){  //see above
    },
    mouseleave:function(){ //see above
    }
    click:function(){ //etc
    }
  });

But I believe the proper use of .on() would be like so:

   $("table.planning_grid").on('mouseenter','td',function(){});

Is there a way to accomplish this? Or what is the best practice here? I tried the code below, but no dice.

$("table.planning_grid").on('td',{
   mouseenter: function(){ /* event1 */ }, 
   mouseleave: function(){ /* event2 */ },
   click: function(){  /* event3 */ }
 });

Thanks in advance!

Answer 1

That's the other way around . You should write:

$("table.planning_grid").on({
    mouseenter: function() {
        // Handle mouseenter...
    },
    mouseleave: function() {
        // Handle mouseleave...
    },
    click: function() {
        // Handle click...
    }
}, "td");

Answer 2

Also, if you had multiple event handlers attached to the same selector executing the same function, you could use

$('table.planning_grid').on('mouseenter mouseleave', function() {
    //JS Code
});

Answer 3

If you want to use the same function on different events the following code block can be used

$('input').on('keyup blur focus', function () {
   //function block
})

Answer 4

I learned something really useful and fundamental from here .

chaining functions is very usefull in this case which works on most jQuery Functions including on function output too.

It works because output of most jQuery functions are the input objects sets so you can use them right away and make it shorter and smarter

function showPhotos() {
    $(this).find("span").slideToggle();
}

$(".photos")
    .on("mouseenter", "li", showPhotos)
    .on("mouseleave", "li", showPhotos);

Answer 5

And you can combine same events/functions in this way:

$("table.planning_grid").on({
    mouseenter: function() {
        // Handle mouseenter...
    },
    mouseleave: function() {
        // Handle mouseleave...
    },
    'click blur paste' : function() {
        // Handle click...
    }
}, "input");

Answer 6

Try with the following code:

$("textarea[id^='options_'],input[id^='options_']").on('keyup onmouseout keydown keypress blur change', 
  function() {

  }
);