$(function() {
    $("#add").focus();
    var list = new Array();
    //Add New Item 
    $("#addItem").click(function() {
        if ($.trim($("#add").val()) != "") {
            list.push($.trim($("#add").val()));
            $("#list").append("<li><input type='checkbox' value='" + (list[list.length - 1]) + "'/>" + list[list.length - 1] + "</li>");
            $("#add").val('');
            if (list.length > 0) {
                $("#list").show(800);
            }

        }

    });
    //Remove Checked Item
    $("#lineThrough").click(function() {
        $("#list input:checked").each(function() {
            var index = $.trim($("#list input:checkbox").index(this));
            alert(index);
            list.splice(index);
            $("#list li:eq(" + index + ")").remove();
            if (list.length <= 0) {
                $("#list").hide('fast');
            }
        });
    });
});

Setting Validate Copy Format

input#add{
  border:1px solid #55669a;
}
button{
  border:1px solid #55669a;
}
button:hover{
  background:#acacac;
}
ol{
  padding:2px;
  border:1px solid #7788a9;
  background:#a2a5fd;
  display:none;
}
ol li{
  list-style:none;
}

Setting Validate Copy Format

<div id="panel">
  <input type="text" id="add" />
  <button name="addItem" id="addItem">
    Add Item
  </button>
  <div>
    <ol id="list">
    </ol>
    <button type="button" name="lineThrough" id="lineThrough">
      Remove Checked Items
    </button>
  </div>
</div>

Copy Format

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