grails acegi ajax登录

js代码如下：

< script type = 'text / javascript' >
// ///ajax登录js
     function  showLogin()  {
        $('ajaxLogin').style.display = 'block';
    }
     function  onSuccessfulLogin(url)  {
        //alert(url);
        document.form1.action=url;
        document.form1.submit();
    }

     function  authAjax()  {
        var form = document.ajaxLoginForm;
        var params = Form.serialize(form)
                + '&spring-security-redirect=/login/ajaxSuccess';
        //Form.disable(form);
        new Ajax.Request(form.action, {
            method : 'POST',
            postBody : params,
            onSuccess : function(response) {
                var responseText = response.responseText || '[]';
                var json = responseText.evalJSON();
                if (json.success) {
                    //alert("ok");
                    onSuccessfulLogin(json.url);
                } else if (json.error) {
                    alert(json.error);
                    Form.enable(document.ajaxLoginForm);
                } else {
                    Element.update('loginMessage', responseText);
                    Form.enable(document.ajaxLoginForm);
                }
            }
        });
    }
</ script >

login代码示例：

def ajaxSuccess  =   {
        nocache(response)
        def config = authenticateService.securityConfig.security
        def postUrl = "${request.contextPath}${config.defaultTargetUrl}"
        render "{success: true,url:'${postUrl}'}"//这里返回的是json
    }



def authfail  =   {

        def username = session[AuthenticationProcessingFilter.SPRING_SECURITY_LAST_USERNAME_KEY]
        def msg = ''
        def exception = session[AbstractProcessingFilter.SPRING_SECURITY_LAST_EXCEPTION_KEY]
        if (exception) {
            if (exception instanceof DisabledException) {
                msg = "[$username] 用户被禁用."
            }
            else {
                msg = "[$username] 错误的用户名或密码."
            }
        }

        if (isAjax()) {
            render "{error: '${msg}'}"
        }
        else {
            flash.message = msg
            redirect action: auth, params: params
        }
    }

页面：
 

<form id="form1" name="form1" target="_blank"></form>

<form action='${request.contextPath}/j_spring_security_check'

    method='POST' id='ajaxLoginForm' name='ajaxLoginForm' target="_blank">

用户名<input id="j_username" name="j_username" type="text" />   

密&nbsp;&nbsp;&nbsp;&nbsp;码<input name="j_password" id="j_password" type="password" /><input onclick='authAjax(); return false;'type="image" src="login.jpg" />

</form>


暂时想不起来为什么用两个form呢，最后引入js:<g:javascript library="prototype" />

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