按下按钮但php不处理

A button is created within a table column by the following code:

print("<td> <button type=\"submit\" name=\"Select_Button\" value=\"Submit\"> Update </ button> </td>");

I want to check if the button was pressed by:

if(isset($_POST['Select_Button']))
{
    print ("Button pressed");
}

How ever when i run the code and press the button nothing happens.

Put else condition as well

 if(isset($_POST['Select_Button'])) 
 { 
     print ("Button pressed");
 }
 else
 {
     echo "Unsuccessful";
 }

<form method="post" action="test1.php" >
<?php
if(isset($_POST['Select_Button']))
{
    print ("Button pressed");
}
print("<td> <button type=\"submit\" name=\"Select_Button\" value=\"Submit\"    `    `> Update </ button> </td>");
?>

</form>

Check if form is there or not ?? without form element the button is not working