jquery programmatically click on new dom element

Question

I am trying to do something tricky (at least to me) in jquery. I have a checkbox that is bound to a function called add_course which looks like this:

    function add_course(){
        var id = $(this).attr('id');
        if ($(this).is(':checked')){

            if($('#courseInput').val().search(id) < 0){
                $('#CourseSummary').append('<span id="cn'+id+'"><a href="#" class="courseDel" id="'+id+'">X</a> '+$('#course'+id+' a').html()+'<br/></span>');
                $('#courseInput').val(function(index,value){
                    return value+ id +',1;';
                });
                addTotal($('#price'+id).text());
            }
            imageSync();
        }else{
            //This is where my question refers to. 
            $('a#'+id+'.courseDel').click();
        }
    }

When someone checks the checkbox, a span with some data and a link are added to the page. The new link is connected to a different function with

$('.courseDel').live('click', del_course); 

del_course does a whole bunch of stuff, just like add_course.

As you can see in the add_course function. I check whether the checkbox has been checked and only do stuff if it has been.

here is del_course:

     function del_course(){
        var id = $(this).attr('id');
        $('#cn'+id).remove();
        $('#courseInput').val(function(index,value){
            return value.replace(id+',1;',"");
        });
        subtractTotal($('#price'+id).text());
        imageSync();
    }

I would like to have the else part of my add_course function trigger the del_course for the corresponding link that got added when the checkbox was checked. This isn't working. I've probably over complicated something.

here is the html for the checkbox (an example of one of them):

<input type="checkbox" class="courseAdd" name="courseAdd" id="204"/>

here is the html for the link that gets added when someone clicks a checkbox:

<span id="cn204"><a href="#" class="courseDel" id="204">X</a> Course Title<br/></span>

It works great when someone clicks the link, but how do i trigger it programatically?

Answer 1

Since you have the ID of the element that you created, simply refernce the ID and use the trigger() method:

$('#'+id).trigger('click');

Also, an ID that is just a number is incorrect:

ID and NAME tokens must begin with a letter ([A-Za-z]) and may be followed by any number of letters, digits ([0-9]), hyphens ("-"), underscores ("_"), colons (":"), and periods (".").

Answer 2

使用jQuery的trigger（）函数。

$('.courseDel').trigger('click');

Answer 3

In the long term, it might help to reorganize your code a bit so that you decouple the DOM event-handling from the application logic.

//Functions to add and remove stuff (these are *not* event handlers)
//Since they now receive explicit parameters
// you have full power over when to add and remove stuff and functions
// can very easily call eachother if needed.

//You can have any kind of state you might need, without having to 
//trick the dom into storing it for you:
var currentlySelectedCourse = null;

function add_course(id){
    //its now easy to access global state like the 
    //currently open course
    //and it is now easy to call other functions like del_course
}

function del_course(id){
}

//event handling can now become just a simple layer...

$('.courseDel').live('click', function(){
     var id = //get the id or what parameters you need
     del_course(id); //pass it to the backend function
});