在中实现层架构物业

public DACustomer(BOCustomer cus)

{

// A reference of the business object class

}

//standard dataset function that adds a new customer

public void Add(BOCustomer cus)

{

String str = BuildAddString(cus);

OpenCnn();

//Open command option - cnn parameter is imporant

OleDbCommand cmd = new OleDbCommand(str,cnn);

//execute connection

ecuteNonQuery();

// close connection

CloseCnn();

}

//standard dataset function that updates

//details of a customer based on ID

public void Update(BOCustomer cus)

{

20多分钟后 OpenCnn();

String selectStr = \"UPDATE \" + thisTable +

\" set \" + cus_LName + \" = \'\'\" + ame + \"\'\'\" +

\", \" + cus_FName + \" = \'\'\" + ame + \"\'\'\" +

\", \" + cus_Address + \" = \'\'\" + dress + \"\'\'\" +

\", \" + cus_Tel + \" = \'\'\" + l + \"\'\'\" +

\" where cus_ID = \'\'\" + sID + \"\'\'\";

OleDbCommand cmd = new OleDbCommand(selectStr,cnn);

ecuteNonQuery();

CloseCnn();

}

//standard dataset function that finds and

//return the detail of a customer in a dataset

public DataSet Find(String argStr)

{

DataSet ds=null;

try

{

OpenCnn();

String selectStr = \"select * from \" + thisTable +

\" where cus_ID = \'\'\" + argStr + \"\'\'\";

OleDbDataAdapter da =

new OleDbDataAdapter(selectStr,cnn);

ds = new DataSet();

ll(ds,thisTable);

CloseCnn();

}

catch(Exception e)

{

String Str = ssage;

}

return ds;

}

private void OpenCnn()

{

// initialise connection

String cnnStr = CnnStr;

cnn = new OleDbConnection(cnnStr);

// open connection

en();

}

private void CloseCnn()

{

// 5- step five

ose();

}

// just a supporting function that builds

// and return the insert string for dataset.

private String BuildAddString(BOCustomer cus)

{

// these are the constants as

// set in the top of this module.

strTable=\"Insert into \" + thisTable;

strFields=\" (\" + cus_ID +

\",\" + cus_LName +

\",\" + cus_FName +

\",\" + cus_Address +

\",\" + cus_Tel + \")\";

//these are the attributes of the

//customer business object.

strValues= \" Values ( \'\'\" + sID +

\"\'\' , \'\'\" + ame +

\"\'\' , \'\'\" + ame +

\"\'\' , \'\'\" + dress +

\"\'\' , \'\'\" + l + \"\'\' )\";

insertStr = strTable + strFields + strValues;

return insertStr;

}

}

}