<input class="easyui-validatebox" data-options="required:true,validType:['email','length[0,20]']">  

$.extend($.fn.validatebox.defaults.rules, {  multiple : {  validator : function(value, vtypes) {  var returnFlag = true;  var opts = $.fn.validatebox.defaults;  for (var i = 0; i < vtypes.length; i++) {  var methodinfo = /([a-zA-Z_]+)(.*)/.exec(vtypes[i]);  var rule = opts.rules[methodinfo[1]];  if (value && rule) {  var parame = eval(methodinfo[2]);  if (!rule["validator"](value, parame)) {  returnFlag = false;  this.message = rule.message;  break;  }  }  }  return returnFlag;  }  },  length : {  validator : function(value, param) {  this.message = 'Please enter a value between {0} and {1}.';  var len = $.trim(value).length;  if (param) {  for (var i = 0; i < param.length; i++) {  this.message = this.message.replace(new RegExp(  "\\{" + i + "\\}", "g"), param[i]);  }  }  return len >= param[0] && len <= param[1];  },  message : 'Please enter a value between {0} and {1}.'  }  });  

调用方法

<input class="easyui-validatebox" data-options="required:true,validType:'multiple[\'email\',\'length[0,20]\']'">  

$.extend($.fn.validatebox.defaults.rules, {  minLength : {  validator : function (value, param) {  var rules = $.fn.validatebox.defaults.rules;  rules.minLength.message = 'Please enter at least {0} characters.';  if(!rules.email.validator(value)){  rules.minLength.message = rules.email.message;  return false;  }  if(!rules.length.validator(value,param)){  rules.minLength.message = rules.length.message;  return false;  }  return value.length >= param[0];  },  message : ''  }
});  

根据方法三的试验：

$.extend($.fn.validatebox.defaults.rules, {//再次输入密码效验（与上一次一样；密码介于6-16位）
    checkpwd: {validator: function (value, param) {var rules = $.fn.validatebox.defaults.rules;rules.checkpwd.message = 'Please enter at least {0} characters.';if (!rules.passequals.validator(value,param)) {rules.checkpwd.message = rules.passequals.message;return false;}if (!rules.minlength.validator(value)) {rules.checkpwd.message = rules.minlength.message;return false;}return value.length >= param[0];},message: ''},passequals: {validator: function (value, param) {return value == $(param[0]).val();},message: '两次密码不一致.'},minlength: {validator: function (value) {var len = $.trim(value).length;return len >=6 && len <= 16;},message: "输入内容长度必须介于6和16之间."}
});

<input id="pwd" name="pwd" type="password" class="easyui-validatebox"  />
<input id="rpwd" name="rpwd" type="password" class="easyui-validatebox" data-options="validType:'checkpwd[pwd]'" />

 idcard: {// 验证身份证
                validator: function (value) {return /^\d{15}(\d{2}[A-Za-z0-9])?$/i.test(value);},message: '身份证号码格式不正确'},minLength: {validator: function (value, param) {return value.length >= param[0];},message: '请输入至少（2）个字符.'},length: { validator: function (value, param) {var len = $.trim(value).length;return len >= param[0] && len <= param[1];},message: "输入内容长度必须介于{0}和{1}之间."},phone: {// 验证电话号码
                validator: function (value) {return /^((\d{2,3})|(\d{3}\-))?(0\d{2,3}|0\d{2,3}-)?[1-9]\d{6,7}(\-\d{1,4})?$/i.test(value);},message: '格式不正确,请使用下面格式:020-88888888'},
mobile: {// 验证手机号码
                validator: function (value) {return /^(13|15|18)\d{9}$/i.test(value);},message: '手机号码格式不正确'},
intOrFloat: {// 验证整数或小数
                validator: function (value) {return /^\d+(\.\d+)?$/i.test(value);},message: '请输入数字，并确保格式正确'},
currency: {// 验证货币
                validator: function (value) {return /^\d+(\.\d+)?$/i.test(value);},message: '货币格式不正确'},
qq: {// 验证QQ,从10000开始
                validator: function (value) {return /^[1-9]\d{4,9}$/i.test(value);},message: 'QQ号码格式不正确'},
integer: {// 验证整数 可正负数
                validator: function (value) {//return /^[+]?[1-9]+\d*$/i.test(value);return /^([+]?[0-9])|([-]?[0-9])+\d*$/i.test(value);},message: '请输入整数'},age: {// 验证年龄
                validator: function (value) {return /^(?:[1-9][0-9]?|1[01][0-9]|120)$/i.test(value);},message: '年龄必须是0到120之间的整数'},chinese: {// 验证中文
                validator: function (value) {return /^[\Α-\￥]+$/i.test(value);},message: '请输入中文'},
english: {// 验证英语
                validator: function (value) {return /^[A-Za-z]+$/i.test(value);},message: '请输入英文'},
unnormal: {// 验证是否包含空格和非法字符
                validator: function (value) {return /.+/i.test(value);},message: '输入值不能为空和包含其他非法字符'},username: {// 验证用户名
                validator: function (value) {return /^[a-zA-Z][a-zA-Z0-9_]{5,15}$/i.test(value);},message: '用户名不合法（字母开头，允许6-16字节，允许字母数字下划线）'},
faxno: {// 验证传真
                validator: function (value) {//            return /^[+]{0,1}(\d){1,3}[ ]?([-]?((\d)|[ ]){1,12})+$/i.test(value);return /^((\d{2,3})|(\d{3}\-))?(0\d{2,3}|0\d{2,3}-)?[1-9]\d{6,7}(\-\d{1,4})?$/i.test(value);},message: '传真号码不正确'},zip: {// 验证邮政编码
                validator: function (value) {return /^[1-9]\d{5}$/i.test(value);},message: '邮政编码格式不正确'},
ip: {// 验证IP地址
                validator: function (value) {return /d+.d+.d+.d+/i.test(value);},message: 'IP地址格式不正确'},
name: {// 验证姓名，可以是中文或英文
                validator: function (value) {return /^[\Α-\￥]+$/i.test(value) | /^\w+[\w\s]+\w+$/i.test(value);},message: '请输入姓名'},
date: {// 验证姓名，可以是中文或英文
                validator: function (value) {//格式yyyy-MM-dd或yyyy-M-dreturn /^(?:(?!0000)[0-9]{4}([-]?)(?:(?:0?[1-9]|1[0-2])\1(?:0?[1-9]|1[0-9]|2[0-8])|(?:0?[13-9]|1[0-2])\1(?:29|30)|(?:0?[13578]|1[02])\1(?:31))|(?:[0-9]{2}(?:0[48]|[2468][048]|[13579][26])|(?:0[48]|[2468][048]|[13579][26])00)([-]?)0?2\2(?:29))$/i.test(value);},message: '清输入合适的日期格式'},
msn: {validator: function (value) {return /^\w+([-+.]\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*$/.test(value);},message: '请输入有效的msn账号(例：abc@hotnail(msn/live).com)'},
same: {validator: function (value, param) {if ($("#" + param[0]).val() != "" && value != "") {return $("#" + param[0]).val() == value;} else {return true;}},message: '两次输入的密码不一致！'}