SqlBulkCopy导入数据（自增列保留原值）

//自增列重新生成：SqlBulkCopy bc = new SqlBulkCopy(conn)
//自增列保留原值：SqlBulkCopy bc = new SqlBulkCopy(conn,SqlBulkCopyOptions.KeepIdentity)
using(SqlBulkCopy sbc = new SqlBulkCopy(conn,SqlBulkCopyOptions.KeepIdentity))
{
    sbc.DestinationTableName = tableName;
    foreach (string col in colList)
    {
        sbc.ColumnMappings.Add(col, col);
    }
    sbc.BulkCopyTimeout = 0;
    sbc.WriteToServer(dt);
}