ajax 与数据库进行数据传输

在页面请求ajax对象，设置相应的参数进行提交，此例是后台进行登录代码的验证：

<tr> <td width="15%" nowrap="nowrap" class="title_item">园区代码</td> <td><html-el:text property="login_code" styleId="login_code" maxlength="20" style="width:200px;" />  <span style="color:#ff0000;" mce_style="color:#ff0000;" id="star">*</span> <span id="loading" style="display:none;" mce_style="display:none;"> <img src="${ctx}/images/loading.gif" mce_src="${ctx}/images/loading.gif" style="vertical-align:middle; margin: 2px;" mce_style="vertical-align:middle; margin: 2px;" />正在处理... </span> </td></tr>

对应js

var xmlHttp = new XMLHttpRequest();var doc = document;$("#login_code").blur(function(){if(this.value.length != 0){var url = "Garden.do?method=getGardenCode&login_code="+this.value;xmlHttp.onreadystatechange = function(){var isExistCode = xmlHttp.responseText;if(xmlHttp.readyState == 4){doc.getElementById("loading").style.display = "none";if(isExistCode == 1){doc.getElementById("star").innerHTML = '<span id="tip" style="color:#FF0000;" mce_style="color:#FF0000;"><img src="${ctx}/images/reg_error.gif" mce_src="${ctx}/images/reg_error.gif" /> 对不起，该园区代码已存在！<//span>';}else{doc.getElementById("star").innerHTML = '<span id="tip" style="color:#5A8E4A;" mce_style="color:#5A8E4A;"><img src="${ctx}/images/reg_success.gif" mce_src="${ctx}/images/reg_success.gif" /> 恭喜，该园区代码可用<//span>';}}else{doc.getElementById("loading").style.display = "";}};xmlHttp.open("POST",url,true);xmlHttp.send(null);

是jquery和script混用的~！~只要觉得方便，怎么整都行

数据请求处理的action请求返回的typeContent类型大概有四种：

1 服务端需要返回一段普通文本给客户端 --text/plain
2 服务端需要返回一段HTML代码给客户端 --text/html
3 服务端需要返回一段XML代码给客户端 --text/xml
4 服务端需要返回一段javascript代码给客户端-- text/javascript
5 服务端需要返回一段json串给客户端 --text/x-json

public ActionForward getGardenCode(ActionMapping mapping, ActionForm form, HttpServletRequest request,HttpServletResponse response) throws Exception {DynaBean dynaBean = (DynaBean) form;String login_code = (String) dynaBean.get("login_code");UserInfo userInfoByCode = new UserInfo();userInfoByCode.setRole_type(new Short("7"));String isExistCode = "null";if (StringUtils.isNotBlank(login_code)) {userInfoByCode.setLogin_code(login_code);if (null == super.getFacade().getUserInfoService().getUserInfo(userInfoByCode)) {isExistCode = String.valueOf("0");} else {isExistCode = String.valueOf("1");}}super.render(response, isExistCode, "text/plain;charset=UTF-8");return null;}

protected void render(HttpServletResponse response, String text, String contentType) {try {response.setContentType(contentType);response.getWriter().write(text);} catch (IOException e) {logger.error(e.getMessage(), e);}}