<!doctype html> <html lang="en"> <head> <meta charset="UTF-8"> <title>获取容器内标签的个数</title> </head> <body> <div class="content" id="content"> <div class="item"><span></span><span></span></div> <div class="item"><span></span><span></span></div> <div class="item"><span></span><span></span></div> <div class="item"><span></span><span></span></div> <div class="item"><span></span><span></span></div> </div> <script src="http://www.jq22.com/jquery/jquery-2.1.1.js"></script> <script type="text/javascript"> window.onload = function(){ var div_l = $(".content").children(".item").length;//JQ获取标签个数方法 console.log("jq方法：",div_l); var div_m = document.getElementById("content"); var div_n = div_m.getElementsByClassName("item").length;//js获取标签个数方法 console.log("js方法：",div_n); } </script> </body> </html>