如何解决类型错误长度未定义

Question

I use jquery 3.0.1. When my code is executed, I receive the error:

TypeError: $(...).length is not a function

How can I solve it?

Code:

$(document).ready(function () {
    size_li = $("#myList li").length();
    x=3;
    $('#myList li:lt('+x+')').show();
    $('#loadMore').click(function () {
        x= (x+5 <= size_li) ? x+5 : size_li;
        $('#myList li:lt('+x+')').show();
    });
    $('#showLess').click(function () {
        x=(x-5<0) ? 3 : x-5;
        $('#myList li').not(':lt('+x+')').hide();
    });
});

Answer 1

it is .length not .length() that is the reason of the error change the line

size_li = $("#myList li").length();

to

size_li = $("#myList li").length;