ACCESS实用技巧：ACCESS的参数化查询

  //temp为Parameter对象可随便定义,OleDbType.VarChar指定为字符串,长度50
  parm.Direction = ParameterDirection.Input;
  //指定其类型输入参数
  cmd.Parameters.Add(parm);
　cmd.Parameters["temp"].Value = "tsing";
  //查询tsing,也可以写成cmd.Parameters[0]
　conn.Open();
　cmd.ExecuteReader();
 

Set parameter = command.CreateParameter (Name, Type, Direction, Size, Value)
参数同上
以下是实例，查询news表中所有tsing发表的新闻
  ------------------------------------------------------
  et conn = Server.CreateObject("Adodb.Connection")
  conn.ConnectionString = connString
  conn.open()
  set mycmd = Server.CreateObject("ADODB.Command")
  mycmd.ActiveConnection=conn
  mycmd.CommandText=sql
  mycmd.Prepared = true
  set mypar = mycmd.CreateParameter("temp",129,1,50,"tsing")
  mycmd.Parameters.Append mypar
  set myrs = mycmd.Execute
 

与上面基本相同不同的地方法是asp在对参数的表达上面不同
  129为adChar，1就是指示输入参数(是其实是默认值)
大家请参阅MICROSOFT的ADOVB.Inc：

  ’----   ParameterDirectionEnum   Values   ----  
  Const   adParamUnknown   =   0  
  Const   adParamInput   =   1  
  Const   adParamOutput   =   2  
  Const   adParamInputOutput   =   3  
  Const   adParamReturnValue   =   4 
’----   DataTypeEnum   Values   ----  
  Const   adEmpty   =   0  
  Const   adTinyInt   =   16  
  Const   adSmallInt   =   2  
  Const   adInteger   =   3  
  Const   adBigInt   =   20  

  Const   adUnsignedTinyInt   =   17  
  Const   adUnsignedSmallInt   =   18  
  Const   adUnsignedInt   =   19  
  Const   adUnsignedBigInt   =   21  
  Const   adSingle   =   4  
  Const   adDouble   =   5  
  Const   adCurrency   =   6  
  Const   adDecimal   =   14  
  Const   adNumeric   =   131  
  Const   adBoolean   =   11  
  Const   adError   =   10  
  Const   adUserDefined   =   132  
  Const   adVariant   =   12  

  Const   adIDispatch   =   9  
  Const   adIUnknown   =   13  
  Const   adGUID   =   72  
  Const   adDate   =   7  
  Const   adDBDate   =   133  
  Const   adDBTime   =   134  
  Const   adDBTimeStamp   =   135  
  Const   adBSTR   =   8  
  Const   adChar   =   129  
  Const   adVarChar   =   200  
  Const   adLongVarChar   =   201  
  Const   adWChar   =   130  
  Const   adVarWChar   =   202  

  Const   adLongVarWChar   =   203  
  Const   adBinary   =   128  
  Const   adVarBinary   =   204  
  Const   adLongVarBinary   =   205

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Data.OleDb;
namespace acc_select
{
    /// <summary>
    /// accselect 的摘要说明
    /// </summary>
    public class accselect
    {
    //"Provider=Microsoft.Jet.OLEDB.4.0; Data Source=d:\dq\db1.mdb"
        private string conn = ConfigurationManager.ConnectionStrings["tsingConnectionString"].ToString();
        public string sql = string.Empty;
        public int t = 4;
        public object v = null;
        public accselect()
        {
        }

        /// <summary>
        /// 构造函数，传递ACC参数查询语句
        /// </summary>
        /// <param name="strsql">strsql字符型</param>
        public accselect(string strsql)
        {
            sql = strsql;
        }
        /// <summary>
        /// 构造函数，传递ACC参数查询语句
        /// </summary>
        /// <param name="strsql">参数查询语句</param>
        /// <param name="total">字节数</param>

        public accselect(string strsql, int total)
        {
            sql = strsql;
            t = total;
        }
        /// <summary>
        /// 构造函数
        /// </summary>
        /// <param name="strsql">参数查询语句</param>
        /// <param name="total">字节数</param>
        /// <param name="value">OBJECT值</param>
        public accselect(string strsql, int total, object value)
        {

            sql = strsql;
            t = total;
            v = value;
        }
        /// <summary>
        ///  getOdd方法返回OleDbDataReader
        /// </summary>
        /// <param name="odt">定义OleDbType类型</param>
        /// <returns></returns>
        public OleDbDataReader getOdd(OleDbType odt)
        {
            OleDbConnection conns = new OleDbConnection(this.conn);
            OleDbCommand cmd = new OleDbCommand(this.sql, conns);

            OleDbParameter parm = new OleDbParameter("temp", odt, this.t);
            parm.Direction = ParameterDirection.Input;
            cmd.Parameters.Add(parm);
            cmd.Parameters[0].Value = this.v;
            conns.Open();
            OleDbDataReader oda = cmd.ExecuteReader();
            cmd.Dispose();
            return oda;
        }
        string Sql
        {
            get

            {
                return sql;
            }
            set
            {
                sql = value;
            }
        }
        int T
        {
            get
            {
                return t;
            }
            set
            {
                t = value;
            }
        }
        object V
        {
            get
            {
                return v;
            }
            set
            {
                v = value;

            }
        }
    }
}
//调用方法
//accselect acc = new accselect();
//acc.sql = "select * from dtt where d_id=?";
//acc.t = 10;
//acc.v = 1;
//OleDbDataReader oda = acc.getOdd(OleDbType.VarChar);
//Repeater1.DataSource = oda;
//Repeater1.DataBind();
 

function acc_sql(sql,adotype,adodct,strlong,values)
dim connstring,mycmd,myrs,conn
 
  connString="Provider=Microsoft.Jet.OLEDB.4.0; Data Source=" & Server.MapPath("db1.mdb")
  set conn = Server.CreateObject("Adodb.Connection")
  conn.ConnectionString = connString
  conn.open()
  set mycmd = Server.CreateObject("ADODB.Command")
  mycmd.ActiveConnection=conn
  mycmd.CommandText=sql
  mycmd.Prepared = true
  set mypar = mycmd.CreateParameter("temp",adotype,adodct,strlong,values)
  mycmd.Parameters.Append mypar
  set myrs = mycmd.Execute
  set acc_sql=myrs 
end function
’调用方法
’dim rs
’sql="select * from users where id=? order by id"
’set rs=acc_sql(sql,3,1,4,1)
’if not rs.eof then
    ’response.Write(rs(1))
’end if