记住用户名

function setCookie(name,value,hours,path){
    var name = escape(name);
    var value = escape(value);
    var expires = new Date();
     expires.setTime(expires.getTime() + hours*3600000);
     path = path == "" ? "" : ";path=" + path;
     _expires = (typeof hours) == "string" ? "" : ";expires=" + expires.toUTCString();
     document.cookie = name + "=" + value + _expires + path;
}

function getCookieValue(name){
    var name = escape(name);
    var allcookies = document.cookie;      
   
     name += "=";
    var pos = allcookies.indexOf(name);   
  
    if (pos != -1){                                            
        var start = pos + name.length;                 
        var end = allcookies.indexOf(";",start);      
        if (end == -1) end = allcookies.length;       
        var value = allcookies.substring(start,end);
        return unescape(value);                        
         }  
    else return "";                              
}

function deleteCookie(name,path){
    var name = escape(name);
    var expires = new Date(0);
     path = path == "" ? "" : ";path=" + path;
     document.cookie = name + "="+ ";expires=" + expires.toUTCString() + path;
}

登录页面加载时：
$(document).ready(function() {
    var userNameValue = getCookieValue("loginName");
    if(userNameValue != ''){
        $("#saveCookie").attr("checked","true");
        $("#loginName").val(userNameValue);
    }else{
        $("#saveCookie").removeAttr("checked");
    }
});

登录按钮提交前：
  if($("#saveCookie").prop("checked"))
        { 
            setCookie("loginName",$("#loginName").val(),24,"/");
        } 
        else{
            deleteCookie("loginName","/");
        }