典型的Jquery Ajax请求示例

$.ajax({
	url: contextPath+"/user/login",
	cache: false,
	type: "POST",
	data: $('#form1').serialize(),
	dataType: "json",
	beforeSend: function(){
		return checkLogin($("#u").val(), $("#p").val());
	},
	success: function(ret){
		if(ret.status == '1'){
			window.location.replace(contextPath + "/main/index");
		} else {
			errorMsg("登录失败",ret.statusInfo)
		}
	},
	error: function(){
		errorMsg("登录失败","服务器异常,请稍后再试");
	}
});