what is extjs data store in root parameter - extjs

Question

I don't have clear idea about extjs 'root' parameter in data store.
var xxx = new Ext.data.JsonStore
({
autoLoad: true,
url: 'www.dataserver.com',
root: 'data',
idProperty: 'ID',
fields: ['ID', 'Name']
});
i feel this very small thing but i'm very new to extjs please explain to me what is use for this root above data tore

Answer 1

It's a config of the JsonReader.
The JsonStore accepts all configs of JsonReader.
In the root config you give the name of the property that'll contain the array of row objects.
In your case it'll be :
{
data: [
{ID: 1, Name: "some name"},
{ID: 2, Name: "another name"}
]
}

Answer 2

Readers are used to interpret data to be loaded into a Model instance or a Store - often in response to an AJAX request. In general there is usually no need to create a Reader instance directly, since a Reader is almost always used together with a Proxy, and is configured using the Proxy's reader configuration property
Ext.create('Ext.data.Store', {
model: 'User',
proxy: {
type: 'ajax',
url : 'users.json',
reader: {
type: 'json',
root: 'users'
}
},
});
The above reader is configured to consume a JSON string that looks something like this:
{
"success": true,
"users": [
{ "name": "User 1" },
{ "name": "User 2" }
]
}
See in the above json structure, we have two attribute(with key:value pair) as "success" amd "users. The "users" key has array of object, which we are going to use in store. so in this json we are going to use the "users" attribute for our reader, so only we mention "users" as root for that store.
As recap, root is the config which will tell which part of attribute/object im going to use for my store in consume json.
Thanks