Sorting By Checking the Option Button PHP MYSQL - php

Question

I want to let the user sort the table base on what the user wants.
I have two options for this, sort by name or sort by exam.
code
echo "<table border=1 align=center><tr class=style2><td><input type=radio name=sort value='byname'>Sort By Name<td><input type=radio name=sort value='byexam'>Sort By Exam";
$sort = $_POST['name'];
if ($sort == "byname"){
$sort=mysql_query("select * from mst_adminresult order by login ASC",$cn) or die(mysql_error());
while($row=mysql_fetch_row($sort))
echo "<table border=1 align=center><tr class=style2><td>Student Name <td> Test<br> Question <td> Score";
echo "<tr class=style8><td>$row[1] <td align=center> $row[2] <td align=center> $row[3]/20";
echo "</table>";
}else{
$sort=mysql_query("select * from mst_adminresult order by test_id ASC",$cn) or die(mysql_error());
while($row=mysql_fetch_row($sort))
echo "<table border=1 align=center><tr class=style2><td>Exam<td width=300>Student Name<td> Score";
echo "<tr class=style8><td>$row[1] <td align=center> $row[2] <td align=center> $row[3]/20";
echo "</table>";
}
echo "<table border=1 align=center><tr class=style2><td width=300>Student Name <td> Test<br> Question <td> Score";
while($row=mysql_fetch_row($rs))
{
echo "<tr class=style8><td>$row[1] <td align=center> $row[2] <td align=center> $row[3]/20";
}
echo "</table>";
the problem I am encountering is it doesn't function properly. The default arrangement of the data is listed by the latest exam taker to the last. Now what I am aiming for is, if the user checks the by the name option, it will sort by name. for the by exam, it will be listed by exam.
output:

Answer 1

Your input radio button name="sort" so you need to use $_POST['sort'].
You can use input value as database field name so that we can easily use it in query without if...else condition.
echo "<table border=1 align=center><tr class=style2>
<tr><td><input type=radio name='sort' value='byname'>Sort By Name</td>
<td><input type=radio name='sort' value='byexam'>Sort By Exam</td></tr></table>";
$sort = isset($_POST['sort']) ? $_POST['sort'] : "test_id"; // change of $_POST['name'] to $_POST['sort']
$sortQuery = mysql_query("select * from mst_adminresult order by ".$sort." ASC",$cn) or die(mysql_error());
while($row=mysql_fetch_row($sortQuery))
{
echo "<table border=1 align=center><tr class=style2><td>Student Name</td><td>Test<br> Question</td><td>Score</td></tr>";
echo "<tr class=style8><td>$row[1]</td> <td align=center> $row[2]</td> <td align=center> ". ($row[3]/20) ."</td></tr> ";
echo "</table>";
}
echo "<table border=1 align=center><tr class=style2><td width=300>Student Name</td><td> Test<br> Question </td><td> Score</td></tr>";
while($row=mysql_fetch_row($rs))
{
echo "<tr class=style8><td>$row[1]</td> <td align=center> $row[2]</td> <td align=center> ". ($row[3]/20) ."</td></tr> ";
}
echo "</table>";