spring 中使用jquery实现ajax异步调用

晨必须的

功能：创建班级前首先检查班级是否存在
 
1.Control类
/**
* 根据班级名查询班级
* @author:qiuchen
* @createTime:2012-6-14
* @param teacherName
* @return
*/
@RequestMapping("/find")
public void findClasses(String clsName,HttpServletResponse response){
PrintWriter writer = null;
try {
writer = response.getWriter();
Classes classes = this.classesService.findByName(clsName);
if(classes == null){
writer.print("ok");
}else{
writer.print("error");
}
} catch (IOException e) {
e.printStackTrace();
} finally{
if(writer != null){
writer.flush();
writer.close();
}
}
}
 
2.JS
var flag = false;
unction check(){
var clsName = document.getElementById("name").value;
var url = "${ctx}/manage/classes/find.do?clsName="+clsName;
$.ajax({type:"POST", url:url,dataType:"text", success:function(datas) {
if(datas == "error"){
document.getElementById("error").style.display = 'inline';
document.getElementById("ok").style.display = 'none';
}else{
document.getElementById("sub").removeAttribute('disabled');
document.getElementById("ok").style.display = 'inline';
document.getElementById("error").style.display = 'none';
flag = true;
}
}});
}