Using an ITable object

NetworkTables works using the ITable interface. See the ITable API Docs for all functionality, but here are some higher level examples on how to use them. See getting a table for instructions on actually getting a table.

Accessing a value

NetworkTables can store the following types of data:

• Bool
• Double
• String
• IList<Bool>
• IList<Double>
• IList<String>
• IList<Byte> (Use for Raw Values)

For any of these, use either the Put### functions to put the data, or the Get### functions to get the data. You can also use the PutValue and GetValue methods to directly get the Value representation of the object.

Persisting a key between restarts

NetworkTables supports making any key persistent between boots. This operation can be performed either on the server, or on any client. To set a key to persistent, call the SetPersistent method for the specific key. To stop a key from being persistent, call ClearPersistent. To check if a key is persistent, call IsPersistent.

Deleting a key

Key deletion is also supported. However note that this feature only works when all clients and the server are based on the NT 3.0 protocol. All versions of NetworkTables after and including the 2016 season support this feature, so most likely this will work for your purpose. To delete a key, call Delete.

Ensuring a key exists in the table

Often times, for configuration values you want the value to be persistent, but also want to ensure a safe default value is used if the persistent values fail to load. In addition, you might want to ensure the values are in the table just to ensure that they can be modified from the dashboard. To enable this, there is a set of functions called SetDefault###. These functions take in a key and a value. If the key already exists in the table, nothing happens, so no data is overwritten. If the key does not exist, the value passed in will be entered into the table.

Working with SubTables

As mentioned in the getting a table doc, subtables can exist in the table. To get a list of all subtables, you can call GetSubTables. You can also check for the existance of an individual subtable with a call to ContainsSubTable. Using GetSubTable you can get an ITable object to the specified subtable, after which all the other operations in this doc can be performed.

Listing all keys

A call to GetKeys will get a list of all keys that exist either in the current table, or in any subtables of the current table. If you want to filter the keys by type in the table, call GetKeys(NtType) with the types as a bitmask of the types you want to get from the query.

Working with Table Listeners

Table listeners are an advanced subject, and can be found on their own TableListner documentation page.