Case and Switch Statement

In the event that a nested If..Then..Else statement becomes complex, a case statement migh just be a better solution. In PHP, the condition is evaluated only once and the expression can only evaluate to a simple data type. http://www.php.net/manual/en/control-structures.switch.php

Example

To post a parcel, the cost is calculated by multiplying the weigh by a rate that depends on the weight. The more the parcel weighs, the greater the rate. For parcels less than 2 kg, the rate is 3.5. For parcels less than 5 kg, the rate is 5.5. Otherwise the rate is 6.5.

<?php

//Calculating parcel freight cost in PHP and designed for use at the command line

fwrite(STDOUT, "Parcel freight cost calculator. \n");

fwrite(STDOUT, "Enter the weight of the parcel  -> ");

fscanf(STDIN, "%d\n", $weight);

Switch ($weight) {

  case 0:

  case 1:

    $rate = 3.5;

    break;

  case 2:

  case 3:

  case 4:

    $rate = 5.5;

    break;

  default:

    $rate = 6.5;

}

$cost = $rate * $weight

fwrite(STDOUT, "The cost to send the parcel is $".$cost."\n");

exit(0);

?>

Note: Any value entered is rounded down to the nearest whole number for comparison.

Exercises

1. Write a program that will display one if 6 different witty comments based on the results of a numbers from 1 to 6 entered by the user.
2. Please add another example
3. Please add another example

This example also has a switch within a switch. Also, there is a a variable $error to monitor whether or not to do the last printout.

<?php

//Displaying text based on string input in PHP and designed for use at the command line

fwrite(STDOUT, "Display the Hexadecimal value of the colours of the rainbow (ROYGBIV) \n\n");

fwrite(STDOUT, "Enter a colour of the rainbow  -> ");

fscanf(STDIN, "%s\n\n", $colour);

$error = 0;

Switch ($colour) {

  case 'red':

    fwrite(STDOUT, "Thats going to be quite a bright red you know. \n");

    $hex = '#FF0000';

    break;

  case 'orange':

    fwrite(STDOUT, "There is quite a few colours of orange \n ");

    fwrite(STDOUT, "Choose one of the following: \n ");

    fwrite(STDOUT, "Orange \n ");

    fwrite(STDOUT, "Darkorange \n ");

    fwrite(STDOUT, "Orangered \n\n --> ");

    fscanf(STDIN, "%s\n\n", $colour);

    Switch ($colour) {

          case 'orange':

            $hex = '#FF9900';

            break;          

          case 'darkorange':

            $hex = '#FF9900';

            break;          

        case 'orangered':

            $hex = '#FF3300';

            break;

          default:

            fwrite(STDOUT, "There are all types of orange... I dont know that one \n");

            $error = 1;

    }

    break;

  case 'yellow':

    $hex = '#FFFF00';

    break;

  case 'green':

    $hex = '#009900';

    break;

  case 'blue':

    $hex = '#0000FF';

    break;

  case 'indigo':

    $hex = '#330099';

    break;

  case 'violet':

    $hex = '#FF99FF';

    break;

  default:

    fwrite(STDOUT, "I dont know that one \n");

    $error = 1;

}

if ($error != 1)

    {

        fwrite(STDOUT, "The Hexidecimal value of " .$colour. ' is ' .$hex. "\n\n");//note multiple \n's create multiple blank lines.

    }

exit(0);

?>

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