<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <title> New Document </title> <meta name="Generator" content="EditPlus" charset=utf-8> <meta name="Author" content=""> <meta name="Keywords" content=""> <meta name="Description" content=""> </head> <body> <table id="tab" width="400" border="1"> <tr><td>序号</td><td>调用数</td></tr> <tr><td>1</td><td>54.2</td></tr> <tr><td>2</td><td>23.9</td></tr> <tr><td>3</td><td>22.1</td></tr> <tr><td>4</td><td>52.9</td></tr> <tr><td>5</td><td>43.2</td></tr> </table> <script> function jisuan(){ var sum = 0; var table = document.getElementById("tab"); for(var i=1;i<table.rows.length;i++){ sum += parseFloat(table.rows[i].cells[1].innerText); } alert(sum); } jisuan(); </script> </body> </html>