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data reader question - ASP.NET General

I'm using 1 connection to open 3 separate data readers to read data into 3 data grids. However, when I try to use the 2nd reader it says that the first reader must be closed. So I use Close() to close it and now it says that 'Object reference not set to an instance of an object' on that line of code. Can anybody help me out with this? SqlConnection objConnection = new SqlConnection(ConfigurationSettings.AppSettings["strConnectTransitTest"] ); //Associated Call Types string strAssocCallTypes; strAssocCallTypes = "SELECT CallType AS 'Call Type', Remark AS 'Description' FROM CallTypeSwitch "; strAssocCallTypes += "WHERE OSValue = " + ...

  1. #1

    Default data reader question

    I'm using 1 connection to open 3 separate data readers to read data into
    3 data grids. However, when I try to use the 2nd reader it says that
    the first reader must be closed. So I use Close() to close it and now
    it says that 'Object reference not set to an instance of an object' on
    that line of code. Can anybody help me out with this?

    SqlConnection objConnection = new
    SqlConnection(ConfigurationSettings.AppSettings["strConnectTransitTest"]
    );

    //Associated Call Types
    string strAssocCallTypes;

    strAssocCallTypes = "SELECT CallType AS 'Call Type', Remark AS
    'Description' FROM CallTypeSwitch ";
    strAssocCallTypes += "WHERE OSValue = " + intIncomingRoute;

    //You must open the connection before populating the DataReader
    objConnection.Open();

    SqlCommand objCommand = new SqlCommand(strAssocCallTypes,
    objConnection);

    //Create/Populate the DataReader
    SqlDataReader objDataReader = null;

    dgAssocCallTypes.DataSource = objCommand.ExecuteReader();
    dgAssocCallTypes.DataBind();

    //can only have 1 data reader open at any one time in 1 connection
    objDataReader.Close();


    Cheers,

    Mike


    *** Sent via Developersdex [url]http://www.developersdex.com[/url] ***
    Don't just participate in USENET...get rewarded for it!
    Mike P Guest

  2. #2

    Default Re: data reader question

    It seems to me that you never create a SqlDataReader instance in the
    objDataReader variable. You declare it, but in the next line, you pass the
    result of ExecuteReader (which gives you back an instance of SqlDataReader)
    to dgAssocCallTypes.DataSource. So objDataReader will still be null. To set
    the datareader variable, you can do this:

    objDataReader = objCommand.ExecuteReader();

    Hope it helps...


    "Mike P" <mrptelcoelectronics.co.uk> wrote in message
    news:OIRBASMXDHA.536TK2MSFTNGP10.phx.gbl...
    > I'm using 1 connection to open 3 separate data readers to read data into
    > 3 data grids. However, when I try to use the 2nd reader it says that
    > the first reader must be closed. So I use Close() to close it and now
    > it says that 'Object reference not set to an instance of an object' on
    > that line of code. Can anybody help me out with this?
    >
    > SqlConnection objConnection = new
    > SqlConnection(ConfigurationSettings.AppSettings["strConnectTransitTest"]
    > );
    >
    > //Associated Call Types
    > string strAssocCallTypes;
    >
    > strAssocCallTypes = "SELECT CallType AS 'Call Type', Remark AS
    > 'Description' FROM CallTypeSwitch ";
    > strAssocCallTypes += "WHERE OSValue = " + intIncomingRoute;
    >
    > //You must open the connection before populating the DataReader
    > objConnection.Open();
    >
    > SqlCommand objCommand = new SqlCommand(strAssocCallTypes,
    > objConnection);
    >
    > //Create/Populate the DataReader
    > SqlDataReader objDataReader = null;
    >
    > dgAssocCallTypes.DataSource = objCommand.ExecuteReader();
    > dgAssocCallTypes.DataBind();
    >
    > //can only have 1 data reader open at any one time in 1 connection
    > objDataReader.Close();
    >
    >
    > Cheers,
    >
    > Mike
    >
    >
    > *** Sent via Developersdex [url]http://www.developersdex.com[/url] ***
    > Don't just participate in USENET...get rewarded for it!

    niceguy Guest

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