自己写的数据库连接类

sql sever的连接类：

<configuration>
    <appSettings>
        <add key="connect" value="Server=(local);database=adventurework;user id=sa;password=123"/>
    </appSettings>
    <connectionStrings/>

 

public class sqlCon
{
    const string strCon;
    public sqlCon()
    {
        strCon = System.Configuration.ConfigurationSettings.AppSettings["connect"];
    }

    public DataSet getData(string sql)
    {
        SqlConnection con = new SqlConnection(strCon);
        SqlDataAdapter adapter = new SqlDataAdapter(sql, con);
        DataSet ds = new DataSet();
        adapter.Fill(ds);
        return ds;
    }

    public string executeScalar(string sql)
    {
        
        SqlConnection con = new SqlConnection(strCon);
        SqlCommand command = new SqlCommand(sql,con);
        command.CommandType = CommandType.Text;
        con.Open();
        string retValue = command.ExecuteScalar().ToString();
        con.Close();
        return retValue;
    }

    public void executeSql(string sql)
    {
        try
        {
            SqlConnection con = new SqlConnection(strCon);
            SqlCommand command = new SqlCommand(sql, con);
            con.Open();
            command.ExecuteNonQuery();
            con.Close();
        }
        catch(Exception ex)
        {
            
        }
    }
}

 

access：

<configuration>
    <appSettings>
        <add key="ConnectString" value="D:\\Visual Studio Projects\\ASP.NET\\myWeb\\student.mdb"></add>
    </appSettings>
    <connectionStrings/>

 

public class MyData
{
    private string strCon;
    public MyData()
    {
        strCon = "provider=microsoft.jet.oledb.4.0;data source=" + 
            System.Configuration.ConfigurationManager.AppSettings["ConnectString"];
    }
    public MyData(string path)
    {
        strCon = "provider=microsoft.jet.oledb.4.0;data source=" + path;
    }
    public DataTable readData(string strSql)
    {
        OleDbConnection odCon = new OleDbConnection(strCon);
        odCon.Open();
        DataSet ds = new DataSet();
        OleDbDataAdapter adapter = new OleDbDataAdapter(strSql, odCon);
        adapter.Fill(ds);
        odCon.Close();
        return ds.Tables[0];
    }
    public void writeData(string strSql)
    {
        OleDbConnection odCon = new OleDbConnection(strCon);
        odCon.Open();
        OleDbCommand cmd = new OleDbCommand(strSql,odCon);
        cmd.ExecuteNonQuery();
        odCon.Close();
    }
}