SQL Query with single quotes
===

getting Error while executing this query , because column text may contain text with single quotes also. How can i use this query w/o any error
My code is

     public bool updateCMStable(int id, string columnName, string columnText)
            {
                try
                {
                    string sql = "UPDATE  CMStable SET " + columnName + "='" + columnText + "' WHERE cmsID=" + id;
                    int i = SqlHelper.ExecuteNonQuery(Connection.ConnectionString, CommandType.Text, sql);
                    if (i > 0)
                    {
                        return true;
                    }
                    else
                    {
                        return false;
                    }
                }
                catch (Exception ee)
                {
                    throw ee;
                }
            } 