从http://www.quirksmode.org/js/cookies.html#script被盗
function createcookie(name,value,days) { if (days) { var date = new Date(); date.setTime(date.getTime()+(days*24*60*60*1000)); var expires = "; expires="+date.toUTCString(); } else var expires = ""; document.cookie = name+"="+value+expires+"; path=/";}function readcookie(name) { var nameEQ = name + "="; var ca = document.cookie.split(';'); for(var i=0;i < ca.length;i++) { var c = ca[i]; while (c.charAt(0)==' ') c = c.substring(1,c.length); if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length); } return null;}function erasecookie(name) { createcookie(name,"",-1);}使用它：
var oldCount = parseInt(readcookie('hitCount'), 10) || 0;createcookie('hitCount', oldCount + 1, 7);如评论中指出的那样，由于cookie被存储并作为字符串返回，因此您应该将其强制转换为int。使用
foo++或
++foo会为您实际投放，但更确切地知道您正在使用的是更安全的方法：
var x = "5"; // x = "5" (string)x += 1; // x = "51" (string!)x += 5; // x = "515" (string!)++x; // x = 516 (number)
