I have this easy programming exercise and I'm trying to do it in PHP: Determine if a student pass or not the course. The student will pass the course if his average of three grades is greater than or equal to 15. Show a message if the student passes or not and validate the three grades before you calculate the average. Show an error message if any grade if wrong.
I have it in both pseudo-code and pseint, so it is easy to validate because I use a do-while loop and everytime it asks me for typing a number and I do it wrong, it validates the grades:
Algorithm Exercise14
Define grade1, grade2, grade3, prom as Real;
Repeat
print "Type the first grade: ";
read grade1;
if (grade1<0 | grade1>20)
print "Error! Invalid grade, type a valid grade.";
endif
Until (grade1>=0 & grade2<=20);
Repeat
print "Type the second grade: ";
read grade2;
if (grade2<0 | grade2>20)
print "Error! Invalid grade, type a valid grade.";
endif
Until (grade2>=0 & grade2<=20);
Repeat
print "Type the third grade: ";
read grade3;
if (grade3<0 | grade3>20)
print "Error! Invalid grade, type a valid grade.";
endif
Until (grade3>=0 & grade3<=20);
prom = (grade1+grade2+grade3)/3;
if (prom>=15)
print "The student passed the course!";
print "The average is: " prom;
else
print "The student did not pass the course.";
print "The average is: " prom;
endif
endAlgorithm
Now, I want to do this but in PHP. My problem is that I cannot validate in this way because if I do it, the browser just takes a lot of time to react and it does nothing, so I have looked on the internet and I need some function to validate but I'm not sure. I'm learning PHP so, excuse me if this is a repeated question or it is to easy but I want to know because I'm learning.
The final question is, how can I validate those fields if I do it with PHP and obviously, HTML5?
PHP code:
<!DOCTYPE html>
<html lang="en">
<head>
<title>Exercise 14</title>
<meta charset="utf-8">
</head>
<body>
<h2>PHP Exercises</h2>
<h3>Exercise 14</h3>
<form action="#" method="post" id="constant" name="constant">
<div>
<label for="text">Grade 1: </label>
<input type="text" name="grade1" placeholder="Type grade1">
</div>
<div>
<label for="text">Grade 2: </label>
<input type="text" name="grade2" placeholder="Type grade 2">
</div>
<div>
<label for="text">Grade 3: </label>
<input type="text" name="grade3" placeholder="Type grade 3">
</div>
<div>
<input type="submit" name="button" id="sending" value="Send">
</div>
</form>
<?php
if(isset($_POST['button'])){
$grade1 = $_POST['grade1'];
$grade2 = $_POST['grade2'];
$grade3 = $_POST['grade3'];
while($grade1<0){
echo "Error!";
}
do{
if ($grade2<0 | $grade2>20) {
echo "Error!";
}
}while($grade2>=0 && $grade2<=20);
do{
if ($grade3<0 | $grade3>20) {
echo "Error!";
}
}while($grade3>=0 && $grade3<=20);
$prom = ($grade1+$grade2+$grade3/3);
if ($prom>=15) {
echo "The averages is: " . $prom;
echo "The student passed the course!";
}else{
echo "The averages is: " . $prom;
echo "The student did not pass the course.";
}
}
?>
</body>
</html>
