Question

I’m fairly new and I need help with PHP, I’m doing a BMI calculator to calculate the BMI of a person by asking for weight and height and preffered system of measurements (metric/imperial), and assesing the user’s BMI (i.e BMI below normal, normal, and above normal), now my problem is that the output keeps giving me two assesment result like this: (please see the img attch’d. below.) ![see img here][1] I have no idea why is it giving me two “Your BMI is above normal” intead of just one. Please see the link to get a better understanding of what I’m trying to say: https://i.stack.imgur.com/EuMFP.jpg

here is my code:

<?php

$weight = $_POST["txtWeight"];
$height = $_POST["txtHeight"];
$unit = $_POST["optUnit"];
$metric = ($weight / ($height * $height));
$imperial = (($weight * 703)/($height * $height));

if ($unit == "metric")
    echo "A height of $height Meters and a weight of $weight Kilograms = " .round($metric,1). " BMI.<br />";

         {
        if($metric <= 18.5)

            echo " Your BMI is below normal";

        else if ($metric >= 18.5 and $metric <= 24.9)

            echo " Your BMI is normal";

        else if($metric >= 25)

            echo " Your BMI is above normal";
        };

if ($unit == "imperial")
    echo "A height of $height Inches and a weight of $weight Pounds = " .round($imperial,1). " BMI.<br />";
        {
        if( $imperial <= 18.5)

            echo "Your BMI is below normal";

        else if ($imperial >= 18.5 and $imperial <= 24.9)

        echo "Your BMI is normal";

        else if($imperial >= 25)

            echo "Your BMI is above normal";
        };              

?>

Answer 1

My guess would be that your brackets are misplaced. Try this:

<?php

$weight = $_POST["txtWeight"];
$height = $_POST["txtHeight"];
$unit = $_POST["optUnit"];
$metric = ($weight / ($height * $height));
$imperial = (($weight * 703)/($height * $height));

if ($unit == "metric") {
  echo "A height of $height Meters and a weight of $weight Kilograms = " . round($metric, 1) . " BMI.<br />";

  if ($metric <= 18.5) {
    echo "Your BMI is below normal";
  } else if ($imperial >= 18.5 && $imperial <= 24.9) {
    echo "Your BMI is normal";
  } else {
    echo "Your BMI is above normal";
  }
}

if ($unit == "imperial") {
  echo "A height of $height Inches and a weight of $weight Pounds = " . round($imperial, 1) . " BMI.<br />";

  if ($imperial <= 18.5) {
    echo "Your BMI is below normal";
  } else if ($imperial >= 18.5 && $imperial <= 24.9) {
    echo "Your BMI is normal";
  } else {
    echo "Your BMI is above normal";
  }
}          

?>

A better approach would be to condense your duplicate code:

<?php

$weight = $_POST["txtWeight"];
$height = $_POST["txtHeight"];
$unit = $_POST["optUnit"];

if ($unit == "metric") {
  echo "A height of $height Meters and a weight of $weight Kilograms = " . round($metric, 1) . " BMI.<br />";
  $bmi = ($weight / ($height * $height));
} else if ($unit == "imperial") {
  echo "A height of $height Inches and a weight of $weight Pounds = " . round($imperial, 1) . " BMI.<br />";
  $bmi = (($weight * 703)/($height * $height));
}

if (isset($bmi)) {
  if ($bmi <= 18.5) {
    echo "Your BMI is below normal";
  } else if ($bmi >= 18.5 && $bmi <= 24.9) {
    echo "Your BMI is normal";
  } else {
    echo "Your BMI is above normal";
  }
}

?>