利用Ext.ux.UploadDialog实现文件下传

var dialog = new Ext.ux.UploadDialog.Dialog({  
		    title:'本地图片上传',  
		    url: '<%=basePath%>shop/link/link_edit!uploadImage.action',  
		    post_var_name:'imageUpload', //参数名
		    reset_on_hide: false,  
		    modal: true,
		    permitted_extensions:['JPG','jpg','JPEG','jpeg','GIF','gif','PNG','png'],  //上传类型限制
		    allow_close_on_upload: true,  //窗口关闭后继续上传
		    upload_autostart: true //是否自动上传
		  }); 
		dialog.show();
		//上传成功后回调函数
		dialog.on('uploadsuccess',function(dialog, filename, resp_data, record){
			//上传成功后，返回的路径,设置在表单imageUrl文本框中
            Ext.getCmp('imageUrl').setValue(resp_data.data.msg);
			//关闭窗口并显示提示信息
            dialog.hide();
            Ext.Msg.alert("系统提示", "文件上传成功！");
		});