Json转义字符的转换

我用的是Ext.decode(),为解析转义字符（\u0000）时出乱码？

{"root":[{"allowBlank":false,"anchor":"","colNo":2,"columnWidth":0,"disabled":false,"enable":true,"fieldArg":"\u0000\u0000\u0001\u0000?\u0000\u0000\u0000\u0000\u0000\u0001\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0016\u0000selectfield\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0003\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000","fieldLabel":"单位","format":"","hidden":false,"hideLabel":false,"id":"UnitName","name":"UnitName","readOnly":true,"regex":"","regexText":"","rowNo":3,"type":"string","value":"","vtype":"","width":"","xtype":"selectfield"},{"allowBlank":true,"anchor":"","colNo":3,"columnWidth":0,"disabled":false,"enable":true,"fieldArg":"","fieldLabel":"单位组","format":"","hidden":false,"hideLabel":false,"id":"UnitGroupName","name":"UnitGroupName","readOnly":true,"regex":"","regexText":"","rowNo":3,"type":"","value":"","vtype":"","width":"","xtype":"textfield"},{"allowBlank":true,"anchor":"","colNo":2,"columnWidth":0,"disabled":false,"enable":true,"fieldArg":"","fieldLabel":"存货属性","format":"","hidden":false,"hideLabel":false,"id":"cInvKName","name":"cInvKName","readOnly":false,"regex":"","regexText":"","rowNo":9,"type":"","value":"","vtype":"","width":"","xtype":"textfield"}],"totalProperty":3}

后台的值是null 吧，先看看你后台的值是否正确

后台是null值啊，Json序列化后null变为转义字符\u0000，那前台js反序列时什么把转义字符反过来，后台是这样的：
List form = (List)this.extjs.getFormPanelField(“unit”);
response.setContentType("application/text/html;charset=utf-8");
response.getWriter().write(ExtHelper.getJsonFromList(form));

你的意思是前台现在显示的是很多 "\u0000" 
现在要去掉它？
调用toString()方法就行

是不是只能转义这些字符
b 退格 
\f 走纸换页 
\n 换行 
\r 回车 
\t 横向跳格 (Ctrl-I) 
\' 单引号 
\" 双引号 
\\ 反斜杠 

其他视为非法，不能转换？

不是去掉它，而是用Ext.decode()直接转换整个字符为对象时出错，你提醒了我，我在数据库里把那个字段值改为""或者为null或者tab时就没问题了。