Jquery method to traverse the checkbox to obtain the value of the selected item_jquery

Source code:

Copy code The code is as follows:

jQuery(function($){
$("input[name='key']:checkbox").click(function(){
var ids = '';
var flag = 0;
$("#ids"). attr("value",ids);
$("input[name='key']:checkbox").each(function(){
if (true == $(this).attr(" checked")) {
ids = $(this).attr('value') ',';
flag = 1;
}
});
if(0 < flag) {
$("#ids").attr("value",ids);
return true;
}else {
alert('Please select at least one item!');
return false;
}
});
});

Function of this source code:

Get the complex value of name='key' The value of the check box, write the value of the selected item into the form of the hidden field.

Core statement:

Copy code The code is as follows:

$(" input[name='key']:checkbox").each(function(){
if (true == $(this).attr("checked")) {
ids = $(this). attr('value') ',';
}
});

In HTML, if a checkbox is checked, the corresponding tag is checked="checked" . But if you use jquery alert($("#id").attr("checked")), you will be prompted that it is "true" instead of "checked", so judge if("checked"==$("#id" ).attr("checked")) is wrong and should be written as above: if(true == $("#id").attr("checked"))