ASP.NET Datareader

68 New Member

Dear Sir/Madam

I would linke you to help me as below:

I want to using datareader and inside datareader I have datareader but I cannot.
I using code as below but error can you help me.

Expand|Select|Wrap|Line Numbers

 Dim Category As String = "SELECT catgcode, catgName FROM tblCategories"

        Dim myCommand As New System.Data.SqlClient.SqlCommand(Category, DBTools.gCnn)

        Dim myReader As System.Data.SqlClient.SqlDataReader=Nothing 

        myReader = myCommand.ExecuteReader()

        While myReader.Read()

           Response.Write("<li><span class='folder'>&nbsp;"& myReader("catgName") &"</span>")

            Dim subCategory As String = "SELECT subCatgCode, subCatgName FROM tblSubCategories WHERE catgcode='"& myReader("catgCode") 

            Dim myCommand1 As New System.Data.SqlClient.SqlCommand(subCategory, DBTools.gCnn)

            Dim myReader1 As System.Data.SqlClient.SqlDataReader

            myReader1 = myCommand1.ExecuteReader()

            While myReader1.Read()

            Response.Write("<ul>")

            Response.Write("<li><span class='file'>&nbsp;"& myReader1("subCatgName") &"</span></li>")

            Response.Write("</ul>")

            End While

            myReader1.Close()

            Response.Write("</li>")

        End While
 
       myReader.Close()

       myReader=Nothing 

    DBTools.gCnn.Close()

thanks
Kosal

Jan 1 '10 #1

Subscribe Reply

2793

tlhintoq

3,525

Recognized Expert Specialist

TIP: When you are writing your question, there is a button on the tool bar that wraps the [code] tags around your copy/pasted code. It helps a bunch. Its the button with a '#' on it. More on tags. They're cool. Check'em out.

Jan 1 '10 #2

tlhintoq

3,525

Recognized Expert Specialist

I using code as below but error

What is the error? On which line of code?

Jan 1 '10 #3

Frinavale

9,735

Recognized Expert Moderator Expert

Well I think that the error is that the content isn't showing up because they are using Response.Write()

Do not use Response.Write() in your VB.NET or C# code.
Why?
Well, it places the content in an invalid place in the page.
For example, if you use Response.Write() in your VB/C# code it's likely that your output is going to look like:

Expand|Select|Wrap|Line Numbers

 
<ul>

 <li><span class='folder'> Folder 1 stuff</span></li>

 <li><span class='folder'> Folder 2 stuff</span></li>

 <li><span class='folder'> Folder 3 stuff</span></li>

 <li><span class='folder'> Folder 4 stuff</span></li>

</ul>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml"> 
 
....

Notice how the content is Above the <html> and doctype tags? This is invalid page content.

Instead of using Response.Write consider using the appropriate ASP.NET controls...like the ListView, or the Repeater control something.

-Frinny

Jan 4 '10 #4

Kosal

New Member

Dear Sir

As above code error:

While myReader1.Read()
Response.Write("<ul>")
Response.Write("<li><span class='file'> "& myReader1("subCatgName") &"</span></li>")
Response.Write("</ul>")
End While

Jan 5 '10 #5

Frinavale

9,735

Recognized Expert Moderator Expert

Kosal, what is the error message?
If there is no error message then please explain what is wrong?

-Frinny

Jan 5 '10 #6

Similar topics

363

Under the hood of DataReader

by: Yasutaka Ito | last post by:

Hi, My friend had a little confusion about the working of DataReader after reading an article from MSDN. Following is a message from him...  I was going thru DataReader...

.NET Framework

750

DataReader

by: Ravi | last post by:

Hi, I am not able to understand why a datareader needs a connection to the DB all the time. Here is what I tried. Sqlcommand cmd = ("select * from table1",con) // where con is the connection...

C# / C Sharp

5747

binding datareader to datagrid in C# windows form

by: Jason Huang | last post by:

Hi, Is it possible to bind DataReader to a DataGrid in C# windows form? And how? And can we update data in a DataSet by using the DataReader? Thanks for help. Jason

C# / C Sharp

467

Reusing DataReader

by: Thomas Scheiderich | last post by:

I have 2 dropdowns that are exactly the same and I don't want to re-read for each. Is there a way to do something like below where I read the data, bind to depCity1 and then bind to destCity2. ...

ASP.NET

5508

DataView vs DataReader

by: Mark | last post by:

Hi all, quick question , a DataView is memory resident "view" of data in a data table therefore once populated you can close the connection to the database. Garbage collection can then be used to...

ASP.NET

1561

Should I use only one public DataReader, or multiple?

by: Andrei Pociu | last post by:

In a typical ASP .NET Web Application (website), I'm currently using a class where I declare some public static objects. For example there's the place where I initialize the SqlConnection. Also...

ASP.NET

3081

Build a dynamic array from DataReader...

by: Brent | last post by:

I'm having a hard time wrapping my head around how to build a multi-dimensional array of n length out of a DataReader loop. Take this pseudo-code: ======================================= public...

ASP.NET

3373

Converting DataReader to a DataTable Performance issue

by: Varangian | last post by:

Hi all, the question I want to ask if the conversion of a DataReader to a Table looping through the DataReader is better than using the Fill Method of the DataAdapter... I'm asking because...

C# / C Sharp

2891

DataReader and DAL

by: Diffident | last post by:

Hello All, I would like to use DataReader based accessing in my Data Access Layer (DAL). What is considered to be a best practice while returning from a DAL method that executes a query and...

ASP.NET

3375

Strange Datareader error

by: Johnny Jörgensen | last post by:

I've got an error that I simply cannot locate: I've got a form in which I use a datareader object to read information from a db. After the read, I close the reader and I dispose of both the...

C# / C Sharp

7160

Problem With Comparison Operator <=> in G++

by: Oralloy | last post by:

Hello folks, I am unable to find appropriate documentation on the type promotion of bit-fields when using the generalised comparison operator "<=>". The problem is that using the GNU compilers,...

C / C++

7196

Maximizing Business Potential: The Nexus of Website Design and Digital Marketing

by: jinu1996 | last post by:

In today's digital age, having a compelling online presence is paramount for businesses aiming to thrive in a competitive landscape. At the heart of this digital strategy lies an intricately woven...

Online Marketing

6878

The easy way to turn off automatic updates for Windows 10/11

by: Hystou | last post by:

Overview: Windows 11 and 10 have less user interface control over operating system update behaviour than previous versions of Windows. In Windows 11 and 10, there is no way to turn off the Windows...

Windows Server

5456

AI Job Threat for Devs

by: agi2029 | last post by:

Let's talk about the concept of autonomous AI software engineers and no-code agents. These AIs are designed to manage the entire lifecycle of a software development project—planning, coding, testing,...

Career Advice

4897

Access Europe - Using VBA to create a class based on a table - Wed 1 May

by: isladogs | last post by:

The next Access Europe User Group meeting will be on Wednesday 1 May 2024 starting at 18:00 UK time (6PM UTC+1) and finishing by 19:30 (7.30PM). In this session, we are pleased to welcome a new...

Microsoft Access / VBA

4583

Couldn’t get equations in html when convert word .docx file to html file in C#.

by: conductexam | last post by:

I have .net C# application in which I am extracting data from word file and save it in database particularly. To store word all data as it is I am converting the whole word file firstly in HTML and...

C# / C Sharp

3088

Trying to create a lan-to-lan vpn between two differents networks

by: TSSRALBI | last post by:

Hello I'm a network technician in training and I need your help. I am currently learning how to create and manage the different types of VPNs and I have a question about LAN-to-LAN VPNs. The...

Networking - Hardware / Configuration

3078

Windows Forms - .Net 8.0

by: adsilva | last post by:

A Windows Forms form does not have the event Unload, like VB6. What one acts like?

Visual Basic .NET

649

How to add payments to a PHP MySQL app.

by: muto222 | last post by:

How can i add a mobile payment intergratation into php mysql website.

PHP