Extjs 里用脚本创建 Hidden字段的代码

今天登录时，需要返回以前来源的地址

String referer = request.getHeader("referer");

在Ext里，使用如下方法指定

new Ext.form.Hidden({
  name:'referer',
  value:'<%=NoNull.toString(referer)%>'
})

这个代码可以放在form的里面，请看完整的代码

<script type="text/javascript">
Ext.onReady(function(){

    Ext.QuickTips.init();

    // turn on validation errors beside the field globally
    Ext.form.Field.prototype.msgTarget = 'side';

    var bd = Ext.getBody();

    /*
     * ================  Simple form  =======================
     */
    //bd.createChild({tag: 'h2', html: 'Form 1 - Very Simple'});


    var simple = new Ext.FormPanel({
        id: 'LOGIN_FORM',
        labelWidth: 75, // label settings here cascade unless overridden
        url:'login.jsp',
        frame:true,
        title: '<font size=3>登录系统</font>',
        bodyStyle:'padding:5px 5px 0',
        width: 350,
        defaults: {width: 230},
        defaultType: 'textfield',
        ctCls: 'font-size:12px', 
        
        items: [{
                fieldLabel: '用户名',
                name: 'username',
                allowBlank:false
            },{
                fieldLabel: '密码',
                name: 'password',
                inputType :'password'
            },new Ext.form.Hidden({
              name:'referer',
              value:'<%=NoNull.toString(referer)%>'
            })
        ],

        buttons: [{
            id: 'submitButton',
            type: 'submit',
            text: '登录',
            tooltip: '点击这个按钮登录系统',
            handler: login
        }]
    });
    simple.render("loginDIV");
});
function login(){
  Ext.Ajax.request({
    url: 'login.jsp',  
    form: 'LOGIN_FORM',
    success: function(t){
      var json = t.responseText.evalJSON();
      if(json.OK=="true"){
        self.location="<%=referer%>";
      }else{
        alert(json.Message);
      }
    }
  });
}
</script>
<div id="LOGIN_FORM_LAYER">
<div id="titleDiv"><img src="images/title.gif"/></div>
<div id="loginDIV"></div>
</div>