//Use the GetPersons method to get all LegalEntities in the BFS instance and write
//the BrickId's and names in the console
var client = new BFSServiceReference.bfsapiSoapClient();
var credentials = new BFSServiceReference.Credentials()
{
    UserName = bfsusername, //Username of administrative user in your instance of BFS
    Password = bfspassword, //Password of the administrative user in your instance of BFS
};
var persons = client.GetPersons(new BFSServiceReference.GetPersonRequest()
{
    Credentials = credentials,
    identify = bfsidentifier, //Identifier is a unique token for your instance of BFS
   
    Fields = new BFSServiceReference.GetPersonFields()
    {
        BrickId = true,
        UserName = true,
        FirstName = true,
        LastName = true,
    },
});
foreach (var c in persons.Result)
{
    Console.WriteLine(c.BrickId + "," + c.FirstName + "," + c.LastName);
}