Programatically using the Business Data Catalog

Yesterday I had to convert an existing SharePoint WebPart from using Microsoft CRM webservices to use the MOSS Business Data Catalog (BDC) as the means of data connection.

I created the following class that may be of use to some people. It builds up a string dictionary of the entity you are searching for. For example if you need to find all the information about a particular organisation pass in the name of the entity "dboAccountBase", the field to search on "AccountID", and the Guid for the organisation. You will be returned a string dictionary containing all the fields for your particular organisation.

 
private Dictionary GetDictionary(string entityName, string filterKey, string filterValue)
{
    Dictionary dict = new Dictionary();
    
    Entity entity = BdcInstance.GetEntities()[entityName]; 
    FilterCollection filters = entity.GetFinderFilters();   
    IEntityInstanceEnumerator enumerator = entity.FindFiltered(filters, BdcInstance);
    
    while (enumerator.MoveNext())
    {
        IEntityInstance iEntity = enumerator.Current;
        DataRow dr = iEntity.EntityAsDataTable.Rows[0];
        
        if ((dr[filterKey] != null || dr[filterKey] != DBNull.Value)
            && (dr[filterKey].ToString().ToUpper() == filterValue.ToUpper()))
        {
            foreach (DataColumn dataColumn in dr.Table.Columns)
            {
                if (dr[dataColumn] == null || dr[dataColumn] == DBNull.Value)
                {
                    dict[dataColumn.ColumnName] = string.Empty;
                }
                else
                {
                    dict[dataColumn.ColumnName] = dr[dataColumn].ToString();
                }
            }
            break;
        }
    }
    return dict;
}

private LobSystemInstance _instance = null;
 
 
private LobSystemInstance BdcInstance
{
    get
    {
        if (_instance == null)
        {
            NamedLobSystemInstanceDictionary sysInstances =  
                ApplicationRegistry.GetLobSystemInstances();
            
            _instance = sysInstances[BdcInstanceName];
        }
        return _instance;
    }
}