private static Exception STSThrowSqlException(SqlException ex)
    {
        Exception STSsqlException = new Exception();
        switch (ex.Number)
        {
            case -2:
                {
                    STSsqlException = new
Exception(STSWebConstants.STS_RequestTimeOut);//Connection   timeout
                    break;
                }
            case 18456:
            case 1326:
                {
                    STSsqlException = new
Exception(STSWebConstants.STS_LoginFailed);//login failed
                    break;
                }
            case 4060:
                {
                    STSsqlException = new
Exception(STSWebConstants.STS_DataBaseNotAvailable);//if    database is not
found
                    break;
                }
            case 229:
                {
                    STSsqlException = new
Exception(STSWebConstants.STS_LoginCredentials);//login    credentials check
                    break;
                }

            case 2601:
            case 2627:
                {
                    STSsqlException = new
Exception(STSWebConstants.STS_UniqueKeyConstraint);//unique    key voilation
                    break;
                }
            case 547:
                {
                    STSsqlException = new
Exception(STSWebConstants.STS_ForeignKeyConstraint);//Foreign    Key
voilation.
                    break;
                }
            default:
                {
                    STSsqlException = new
Exception(STSWebConstants.STS_UnKnowException);//any other    exceptions
                    break;
                }
        }
        return STSsqlException;
    }