请教extjs store jsonp 使用出错的问题

先来看看Store的load()方法
load( Object options ) : void
Parameters:
options : Object
An object containing properties which control loading options:
r : Ext.data.Record[]
options: Options object from the load call
success: Boolean success indicator
params :Object
An object containing properties to pass as HTTP parameters to a remote data source.
callback : Function}
A function to be called after the Records have been loaded. The callback is passed the following arguments:

scope : Object
Scope with which to call the callback (defaults to the Store object)
add : Boolean
Indicator to append loaded records rather than replace the current cache.
Returns:
void
由上可知，可以很轻松的写出Store异常处理
ds.load({params:{start:0, limit:4},
callback:function(r, options, success) {
if (success == false) {
Ext.Msg.alert('错误','数据提取错误') ; //当然也可以做其他的处理操作
}else{
Ext.Msg.alert('提示,'数据提取成功)
}
}
});
出错信息可以在options.request.scope.reader.jsonData 或 options.request.scope.reader.rawData 中获得。