Chrome console handling jQuery $(this) bug?

It is kind of strange.

<table>
    <tr>
        <td>feng</td>
    </tr>
</table>

jQuery code:

$('table tr').click(function(e){
   console.log($(this)==null); //returns False
});开发者_Python百科

The Chrome console outputs False, which is expected. However, when I toggle a break point in the function and trigger the event, I found that ,if I type $(this) in the Chrome console, it returns null

The this "variable" isn't really a variable. I don't think Chrome establishes a value for this to match that in the current execution context; it'd be pretty hard to do that, frankly.

If you want to be able to debug such a function, just make sure you put the this value into a regular old local variable:

   var saveThis = this;

Then, $(saveThis) should work for you.

I usually find it handy to save "this" when I plan to pass it to another function.

var $this = $(this);