jQuery live（）函数，用于大量使用ajax网站

Question

Ive been looking for a way to make sure all scripts are triggered accordingly as content is loaded in and out of the page via jQuery load.

The best method so far is the live function but I cannot get it to trigger functions on load, only operate with elements loaded in.

EG.

$(document).ready(function(){
    $('textarea').live('keyup',function(){
        $(this).innerHeight(20 + (16 * ($(this).prop('scrollHeight') / $(this).css('line-height').replace('px', '') - 1.25)));
    });
    $('textarea').trigger('keyup');
});

This will make the textarea perform correctly on the keyup function but will not trigger the initial $('textarea').keyup();

How would I do that / is there a better way of achieving what I am after.`

I have got this far but my initial call does not work once the page has loaded:

$(document).ready(function(){
    $(document).on('keyup', 'textarea',function(){
        $(this).innerHeight(20 + (16 * ($(this).prop('scrollHeight') / $(this).css('line-height').replace('px', '') - 1.25)));
    });
    $('textarea').trigger('keyup');
});

Answer 1

First, you want to use trigger() to fire an event.

Also, don't use live() because it's deprecated. Instead use on() . The syntax slightly changes:

$(document).ready(function(){
    $(document).on('keyup', 'textarea', function(){
        $(this).innerHeight(20 + (16 * ($(this).prop('scrollHeight') / $(this).css('line-height').replace('px', '') - 1.25)));
    });
    $('textarea').trigger('keyup');
});

The selector in $(document).on('keyup', 'textarea', function) works as follows:

1. Look for elements in document that are matching textarea (this also works for elements that are added after page load)
2. If the keyup event is triggered, execute the callback method

Therefore, you can write something more specific than document to decrease the computation time. For example:

$('#myForm').on('keyup', 'textarea', function)

Answer 2

Alp's response works perfectly. The handler fires when you use trigger() so I don't understand where you're getting your error.

Be sure that you trigger the keyup on your textarea AFTER you have loaded whatever dynamic content you are populating it with. If you are using jQuery's load() to bring in content, trigger the keyup in the callback function.

JS Fiddle