動軟—更新的仅仅是其中一个字段，则其他字段都会被更新为空字符。

解决的办法，是将其修改为：
01./// <summary>   
02.        /// 更新一条数据   
03.        /// </summary>   
04.        public void Update(Maticsoft.Model.payment model)  
05.        {  
06.            StringBuilder strSql=new StringBuilder();  
07.            strSql.Append("update payment set ");  
08.            strSql.Append("fj_id=ISNULL(@fj_id,fj_id),");  
09.            strSql.Append("pay_amount=ISNULL(@pay_amount,pay_amount),");  
10.            strSql.Append("pay_date=ISNULL(@pay_date,pay_date),");  
11.            strSql.Append("purpose=ISNULL(@purpose,purpose),");  
12.            strSql.Append("verify=ISNULL(@verify,verify),");  
13.            strSql.Append(" where id=@id ");  
14.            SqlParameter[] parameters = {  
15.                    new SqlParameter("@id", SqlDbType.Int,4),  
16.                    new SqlParameter("@fj_id", SqlDbType.Int,4),  
17.                    new SqlParameter("@pay_amount", SqlDbType.Money,8),  
18.                    new SqlParameter("@pay_date", SqlDbType.DateTime),  
19.                new SqlParameter("@purpose", SqlDbType.VarChar,50),  
20.                    new SqlParameter("@verify", SqlDbType.Bit)};  
21.            parameters[0].Value = model.id;  
22.            parameters[1].Value = model.fj_id;  
23.            parameters[2].Value = model.pay_amount;  
24.            parameters[3].Value = model.pay_date;  
25.            parameters[4].Value = model.purpose;  
26.            parameters[5].Value = model.verify;  
27.            DbHelperSQL.ExecuteSql(strSql.ToString(),parameters);  
28.        }