How do i...compare selected radio buttons and answer in the database in ASP.NET and C#

Question

0.00/5 (No votes)

See more:

hey guys iam developing online examination website using asp.net and c# but in the result.aspx page i want to compare the selected option and answer in the database so this is my code and its not working and not displaying any thing

What I have tried:

// submitt button click event

protected void Exambutton_Click(object sender, EventArgs e)
{
SqlCommand cmd = new SqlCommand("Select Answer from [Biology]", con);
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataTable ddt = new DataTable();
da.Fill(ddt);
if (QuestionGrid.FindControl("Option1") == ddt.Rows[0]["Answer"])
{
result = 1;
resultlabel.Text = result.ToString();

}

Posted 4-Dec-18 19:23pm

AhmedHosny96

Updated 5-Dec-18 13:32pm

Add a Solution

Comments

F-ES Sitecore 5-Dec-18 5:21am

FindControl returns an object that encapsulates the control, if your case a radio button probably. Rows[0]["Answer"] is probably text however. You can't compare an object to text, what you want to do is compare the selected value that Option1 represents with the answer.

Google how to use FindControl to cast to a specific control.

2 solutions

Solution 1

are we assuming here your table 'biology' only contains one row?

Posted 5-Dec-18 2:58am

RmcbainTheThird

Comments

AhmedHosny96 5-Dec-18 10:26am

yes brother my table here is biology i need to compare all the 4 radiobuttons with correct answer in the database and then display the result ?

Vincent Maverick Durano 5-Dec-18 19:07pm

Please use the "Have a Question or Comment" button when asking for clarification instead of posting it as a solution.

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Vincent Maverick Durano · Accepted Answer · 2018-12-05T13:32:00

First off, make it a habit to put objects that eat resources such as SqlConnection, SqlCommand and SqlDataAdapter within a using statement to ensure that objects will be properly disposed and closed after they are used.

Second, if your QuestionGrid is a GridView, then you can't just use FindControl() method directly to it since a GridView is composed of Rows and Columns. This means that you need to traverse to its rows first before using FindControl.

Third, you can't compare the result of FindControl() method to a string. So this line if (QuestionGrid.FindControl("Option1") == ddt.Rows[0]["Answer"]) of code will fail.

Here's what you can try:

C#

protected void Exambutton_Click(object sender, EventArgs e)
{
	DataTable dt = new DataTable();
	string sqlStatement = "SELECT Answer FROM [Biology]";
   
        	using(SqlConnection connection = new SqlConnection("Your Connection String from your Web.config")){
           		using(SqlCommand cmd = new SqlCommand(sqlStatement ,connection)){
               	 	cmd.CommandType = CommandType.Text;
					using(SqlDataAdapter da = new SqlDataAdapter(cmd)){
						da.Fill(dt);
						if(dt.Rows.Count > 0){
							int index = 0;
							foreach (GridViewRow row in QuestionGrid.Rows){
								RadioButton rb = (RadioButon) row.FindControl("Option1");
								if(rb != null){
									if(rb.Text == dt.Rows[index]["Answer"]){
										//do something if matched
										rb.Checked = true;
									}
								}
								index++;
							}
						}
						else{
							//No Records found	
						}
					}
        		}
        }
}