EXTJS JsOnStore bit but display blank value

问题

This is an Picture Show PowerOff Return value with \u0001 , but unfortunately when i store in JsOnStore are failure and i m trying to alert('PowerOff') are blank, why?

this is my JsOnStore Model Data

Ext.define('GoogleMarkerModel', {
        extend: 'Ext.data.Model',
        fields: [
        {name: 'ID',    type: 'int'},
        {name: 'Locating',    type: 'int'},
        {name: 'MainPower',    type: 'int'},
        {name: 'Acc',    type: 'int'},
        {name: 'PowerOff',    type: 'int'}, // i have tried int,string,bit
        {name: 'Alarm',    type: 'int'},
        {name: 'Speed',    type: 'int'},
        {name: 'Direction',    type: 'int'},
        {name: 'Latitude',    type: 'float'},
        {name: 'Longitude',    type: 'float'},
        {name: 'DateTime',    type: 'datetime'},
        {name: 'MainID',    type: 'int'},
        {name: 'IOState',    type: 'int'},
        {name: 'OilState',    type: 'int'},
        {name: 'PicUploadedDateTime',    type: 'datetime'},
        {name: 'PicData',    type: 'str'}
        ]
    });

来源：https://stackoverflow.com/questions/18108760/extjs-jsonstore-bit-but-display-blank-value