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ee-itpro

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Generate Dropdownlists dynamically and bind data from datatable or dataadapter methods

Hi,
     I'm  not much experienced with asp.net development.  I have a database for a kind of quiz application, answers to which are then processed through logic to generate or determine a plan for the user.

I have two tables in the database 1)Questions  table with Qid(P key), Q description etc.

2)QuestionAns table which contains all the answer options for every question in the question table.   Columns are QueAnsId(P. Key),Qid(foreign key), Answers(all answers options for every question).

I created two datasets for each of these tables using the configuration wizards. 1)QuesDS,
2)AnsDS

On their respective tableAdapters, i have written methods GetQuestions(), GetAnswersByQuesId(Qid)containg respective sql queries.

What i want to achieve is,  for each question  displayed , a dropdownlist with all the answer options for that question be displayed. Then a question again and A dropdownlist again and so on.  The answer dropdownlists should be  generated dynamically based on number of questions  in the question table. I can get the questions to print but not the answers list.

My questions are:

1)Is a Dataset solution appropriate for this or should i be using a datareader?
2)Am i on the right track  or is this the appropriate way of what i am trying to achieve?
3)Get the dropdownlists to work.


Code for this follows below:

using.........default namespaces.......
using QuesDSTableAdapters;
using AnsDSTableAdapters;


public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {


        QuesDSTableAdapters.QuestionTableAdapter questionsAdapter = new
 QuesDSTableAdapters.QuestionTableAdapter();

        QuesDS.QuestionDataTable questions;

        questions = questionsAdapter.GetQuestions();



        AnsDSTableAdapters.QueAnsTableAdapter queansAdapter = new
 AnsDSTableAdapters.QueAnsTableAdapter();

 AnsDS.QueAnsDataTable answer;

               // AnsDS.QueAnsDataTable queans;


foreach (QuesDS.QuestionRow quesRow in questions)
        {


            Response.Write("Question: " + quesRow.Que + "<br />");

            answer = queansAdapter.GetAnswersByQuestionId(quesRow.QID);

            DropDownList ddl = new DropDownList() ;

            // ddl.DataSource = queansAdapter.GetAnswersByQuestionId(Convert.ToInt32(quesRow.QID));

           
ddl.DataSource = answer;

           // DropDownList1.Items.Add(Convert.ToString(answer.Columns ["Answer"]));

ddl.DataTextField  = "Answer";

            ddl.DataBind();
           


        }

    }

Avatar of urir10
urir10

Are you getting anything for the answer DDL?
Avatar of ee-itpro

ASKER

Didn't understand that.
Are you getting anything to show in the Drop Down List for the answers or does it just remain blank?
Remains blank and shows after the two questions that i have currently in  question table.  It should show like ques and then ans nad then ques again and ans again.
You mean the control itself shows after the two questions are printed? if so you need to add the control to the from within the foreach loop
Yes after the two questions are printed.  
Where is the line where you adding the control to the page?
i just have it in design view.... how do we add it the code?
i added it just now like this :

DropDownList ddl=new DropDownlist();

form.controls.add(ddl);


Now it shows the lists but there are 3 instead of 2 for 2 questions and they all show in a horizontal line and after the printed questions.
you can add this between each control and each question to break the line:

form.controls.Add(new LiteralControl("<br/>"));

As to it adding it 3 times it must be something in the loop that makes it run 3 times instead ok.
the dropdownlists still appear after the questions
can you post your complete code again pls
public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {


        QuesDSTableAdapters.QuestionTableAdapter questionsAdapter = new
 QuesDSTableAdapters.QuestionTableAdapter();
        QuesDS.QuestionDataTable questions;

        questions = questionsAdapter.GetQuestions();



        AnsDSTableAdapters.QueAnsTableAdapter queansAdapter = new
 AnsDSTableAdapters.QueAnsTableAdapter();

        AnsDS.QueAnsDataTable answer;

       

       // AnsDS.QueAnsDataTable queans;

       




        foreach (QuesDS.QuestionRow quesRow in questions)
        {


            Response.Write("Question: " + quesRow.Que + "<br />");



           answer = queansAdapter.GetAnswersByQuestionId(quesRow.QID);

           Form.Controls.Add(new LiteralControl("<br/>"));

            DropDownList ddl = new DropDownList();


           


            Form.Controls.Add(ddl);

            // ddl.DataSource = queansAdapter.GetAnswersByQuestionId(Convert.ToInt32(quesRow.QID));

            ddl.DataSource = answer;

           // DropDownList1.Items.Add(Convert.ToString(answer.Columns ["Answer"]));
            ddl.DataTextField  = "Answer";
            ddl.DataBind();

           
           
        }

    }
    protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
    {

    }
}
i still dont see where are you adding the control to the page?
after i create the dropdownlist object, then i write

form.control.add(ddl),


where ddl is the dropdownlisty object i created .
ASKER CERTIFIED SOLUTION
Avatar of urir10
urir10

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i added form.control.aa(new literal control........)  in between  ques and ans and also twice before the end of foreach loop. So now it displays better.  But there's still a empty drop downlist that appears  just before the first question.


 foreach (PLabDS.QuestionRow quesRow in questions)
        {


            //Response.Write("Question: " + quesRow.Que + "<br />");



           //answer = queansAdapter.GetAnswersByQuestionId(quesRow.QID);

           Form.Controls.Add(new LiteralControl(quesRow.Que));

           answer = queansAdapter.GetAnswersByQuestionId(quesRow.QID);

            DropDownList ddl = new DropDownList();


            Form.Controls.Add(new LiteralControl("<br>"));


            Form.Controls.Add(ddl);

            // ddl.DataSource = queansAdapter.GetAnswersByQuestionId(Convert.ToInt32(quesRow.QID));

            ddl.DataSource = answer;

           // DropDownList1.Items.Add(Convert.ToString(answer.Columns ["Answer"]));
            ddl.DataTextField  = "Answer";
            ddl.DataBind();

            Form.Controls.Add(new LiteralControl("<br>"));

            Form.Controls.Add(new LiteralControl("<br>"));
           
        }
deleted the list control from design view . it's working fine now...


i'll accept the solution.



can you just tell me if i am using the right approach (datasets  instead of datareader for this particular scenario)?
deleted the list control from design view . it's working fine now...


i'll accept the solution.



can you just tell me if i am using the right approach (datasets  instead of datareader for this particular scenario)?
Yes a dataset or a datatables are just fine.