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ACCESS的參數化查詢
ASP.NET C#語法
OleDbParameter parm = new OleDbParameter(Name, Type, Direction, Size, Value);
(實際上它有七重載大家具體大家可以在VS.net裡面就可以看到)
參數
Name 可選，字符串，代表 Parameter 對象名稱。
Type 可選，長整型值，指定 Parameter 對象數據類型。
Direction 可選，長整型值，指定 Parameter 對象類型。。
Size 可選，長整型值，指定參數值最大長度（以字符或字節數為單位）。
Value 可選，變體型，指定 Parameter 對象的值。
以下是實例，查詢news表中所有tsing發表的新聞
-------------------------------------------------------
sql="select * from newss where username=? order by id"
//注意查詢的條件均用?號表示
OleDbConnection conn = new OleDbConnection(connString);
OleDbCommand cmd = new OleDbCommand(sql,conn);
OleDbParameter parm = new OleDbParameter("temp",OleDbType.VarChar, 50);
//temp為Parameter對象可隨便定義,OleDbType.VarChar指定為字符串,長度50
parm.Direction = ParameterDirection.Input;
//指定其類型輸入參數
cmd.Parameters.Add(parm);
cmd.Parameters["temp"].Value = "tsing";
//查詢tsing,也可以寫成cmd.Parameters[0]
conn.Open();
cmd.ExecuteReader();
ASP VBSCRIPT語法
Set parameter = command.CreateParameter (Name, Type, Direction, Size, Value)
參數同上
以下是實例，查詢news表中所有tsing發表的新聞
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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
與上面基本相同不同的地方法是asp在對參數的表達上面不同
129為adChar，1就是指示輸入參數(是其實是默認值)
大家請參閱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
附C#類，和VBSCRIPT函數，希望對大家有幫助
using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Data.OleDb;
namespace acc_select
{
/// <summary>
/// accselect 的摘要說明
/// </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>
/// 構造函數，傳遞ACC參數查詢語句
/// </summary>
/// <param name="strsql">strsql字符型</param>
public accselect(string strsql)
{
sql = strsql;
}
/// <summary>
/// 構造函數，傳遞ACC參數查詢語句
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