Trying PHP IF Else Statements for the first time - php

Question

I'm learning PHP and trying to understand the if .. else statements a little better, so I'm creating a little quiz. However, I have come across an issue and I don't seem to know what the issue is. My problem is that whenever I type in the age in the input area, it will give me the $yes variable every time even if I enter the wrong age.
Here is my code so far:
My html file:
<form action="questions.php" method="post">
<p>How old is Kenny?<input></input>
<input type="submit" name="age" value="Submit"/>
</p></form>
My php file:
<?php
$age = 25;
$yes = "Awesome! Congrats!";
$no = "haha try again";
if ($age == 25){
echo "$yes";
}else{
echo "$no";
}
?>

Answer 1

You catch the user input inside the $_POST superglobal var (because the method of your form is POST.
So
<?php
$age = 25;
should be
<?php
$age = $_POST['age'];
There is an error in HTML too. This
<input type="submit" name="age" value="Submit"/>
should be
<input type="text" name="age" value=""/>
<input type="submit" value="Click to submit"/>
Because you want one input and one button. So one html element for each element.
and <input></input> must be cleared because it's not valid syntax :-)

Answer 2

<form action="questions.php" method="post">
<p>How old is Kenny?</p><input type="text" name="age"></input>
<input type="submit" value="Submit"/>
</form>
$age = (int) $_POST["age"];
$yes = "Awesome! Congrats!";
$no = "haha try again";
if ($age == 25) {
echo $yes;
} else {
echo $no;
}

Answer 3

<?php
/* Test that the request is made via POST and that the age has been submitted too */
if( $_SERVER['REQUEST_METHOD']=='POST' && isset( $_POST['age'] ) ){
/*
ensure the age is an integer rather than a string ..
though for this not overly important
*/
$age=intval( $_POST['age'] );
if( $age==25 ) echo "Congratulations";
else echo "Bad luck!";
}
?>
<form action="questions.php" method="post">
<p>How old is Kenny?
<input type='text' name='age' placeholder='eg: 16' />
<input type="submit" value="Submit" />
</p>
</form>
A simple html form, note that the submit button does not carry the values you want to process, they are supplied via the input text element.

Answer 4

First of all, you need to echo the variable; echoing "$no" will keep it as a string. Remove the quotes from "$no" and "$yes" in your if then statement. Otherwise, your code seems sound!