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Servlets - Radio button check uncheck validation?

Hello friends over this media! ,

I am stuck here with a servlet in which i am trying to generate a online quiz . I genearated radio buttons dynamically depending on the data from the database.i.e., there's a table which has 5 columns namely, question, choice1,choice2, choice3,choice4. I am able to generate the buttons but am not able to read the value of the checked radio button. Though the default button is checked it's still not printing the value. I have the HTML code inside this servlet itself. I have'nt written it separately because i have to generate radio buttons depending on the number of rows in the database. Please help me out....:-(! Here 's the code attached!

/***** part of dopost method**********/
/*Am using a MsqlJava package to connect and retrieve data from the
database. ***/
/***qans is the table ******/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {

String row1[],row2[],row3[],row4[],row5[];

MsqlResult result1=msql.Query("select question from qans");
MsqlResult result2=msql.Query("select answer1 from qans");
MsqlResult result3=msql.Query("select answer2 from qans");
MsqlResult result4=msql.Query("select answer3 from qans");
MsqlResult result5=msql.Query("select answer4 from qans");

/***Just checking for one row fetched from the database*****/
if ((row1 = result1.FetchRow()) != null && (row2 = result2.FetchRow()) != null && (row3 = result3.FetchRow()) != null && (row4 = result4.FetchRow()) != null && (row5 = result5.FetchRow()) != null)
      {
            for(i=0; i < row1.length; i++)
            for(j=0; j < row2.length; j++)
            for(k=0; k < row3.length; k++)
            for(l=0; l < row4.length; l++)
            for(m=0; m < row5.length; m++)

toClient.println("<font size=3 color=navy>" + row1[i] + "<BR><BR><INPUT TYPE=RADIO NAME=" + a[inc] + " VALUE=" + row2[j] + " checked >" + row2[j] + "<BR><INPUT TYPE=RADIO NAME=" + a[inc] + " VALUE=" + row3[k] + ">" + row3[k] + "<BR><INPUT TYPE=RADIO NAME=" + a[inc] + " VALUE=" + row4[l] + ">" + row4[l] + "<BR><INPUT TYPE=RADIO NAME=" + a[inc] + " VALUE=" + row5[m] + ">" + row5[m] +"</font><br><br>");

      String value = request.getParameter("a[inc]");
toClient.println(value);
/**********Prints a null value when run**************/
            inc++;
            }

}

sgoms

Seperate your logic..
/**GenerateServlet.java**/
have the servlet generate the form dynamically
in the form action method call a servlet called 'ProcessDataServlet' in that process ur answers.

GenerateHTMLServlet
->
<FORM NAME=Quiz ACTION="/servlet/ProcessDataServlet">
....

->
/**ProcessDataServlet.java**/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String ans=request.getParameter("Radio button name");

}

you cannot have the checking in the same method 'cos once the HTML response is sent to the browser the html page has to contact the servlet again for the data to be processed.
-sgoms

smithan

ASKER

thanks a lot sgoms! It works now!

ASKER CERTIFIED SOLUTION

sgoms

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