This code example shows how a BizForm record can be deleted.
[C#]
| using CMS.FormEngine; using CMS.SettingsProvider; using CMS.DataEngine; using CMS.GlobalHelper; 
 ... 
 string bizFormName = "TestingSiteContactUs"; string siteName = "CMSTestingSite"; 
 // Get BizForm definition BizFormInfo bfi = BizFormInfoProvider.GetBizFormInfo(bizFormName, siteName); 
 if (bfi != null) { // Get data type definition DataClassInfo dci = DataClassInfoProvider.GetDataClass(bfi.FormClassID); if (dci != null) { // Get all bizform data GeneralConnection genConn = ConnectionHelper.GetConnection(); DataSet ds = genConn.ExecuteQuery(dci.ClassName + ".selectall", null, null, null); 
 if (!DataHelper.DataSourceIsEmpty(ds)) { // Get ID of the first record int formRecordID = ValidationHelper.GetInteger(ds.Tables[0].Rows[0][0], 0); // Get the record with specified ID DataClass formRecord = new DataClass(dci.ClassName, formRecordID, genConn); 
 if (!formRecord.IsEmpty()) { // Delete the first record. formRecord.Delete(); 
 // Update number of entries in BizFormInfo bfi.FormItems--; BizFormInfoProvider.SetBizFormInfo(bfi); 
 lblInfo.Text = "The record was deleted successfully."; } } else { lblInfo.Text = "No data found."; } } } | 
Page url: http://devnet.kentico.com/docs/5_5r2/devguide/index.html?api_bizforms_deleting_a_record.htm