拼命工作好好玩 2019-03-31
代码如下:
OleDbParameter parm = new OleDbParameter(Name, Type, Direction, Size, Value);
(实际上它有七重载大家具体大家可以在VS.net里面就可以看到)
参数
Name 可选,字符串,代表 Parameter 对象名称。
Type 可选,长整型值,指定 Parameter 对象数据类型。
Direction 可选,长整型值,指定 Parameter 对象类型。。
Size 可选,长整型值,指定参数值最大长度(以字符或字节数为单位)。
Value 可选,变体型,指定 Parameter 对象的值。
以下是实例,查询news表中所有tsing发表的新闻
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sql="select * from newss where username=? order by id"
//注意查询的条件均用?号表示
OleDbConnection conn = new OleDbConnection(connString);
OleDbCommand cmd = new OleDbCommand(sql,conn);
OleDbParameter parm = new OleDbParameter("temp",OleDbType.VarChar, 50);
//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(); 代码如下:
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
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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 代码如下:
'---- 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