Aims:
salary_form.html
contains this form:
<form action="tax.php" method="get"> <input type="text" name="salary" value="0" /> <input type="submit" /> </form>
tax.php
(next slide), which outputs the amount of tax the user must pay
at each rate
tax.php
$salary = (int) $_GET['salary']; $tax_paid_at_lower_rate = 0.0; $tax_paid_at_higher_rate = 0.0; if echo "<table>"; echo "<tr><th>Tax paid at lower rate</td><td>{$tax_paid_at_lower_rate}</td></tr>"; echo "<tr><td>Tax paid at higher rate</td><td>{$tax_paid_at_higher_rate}</td></tr>"; echo "</table>";
tax.php
?
echo
statements to see what gets reachedvar_dump
to inspect the type and contents of variablestax.php
by a programmer
who has chosen to avoid two-armed conditionals
tax.php
$salary = (int) $_GET['salary']; $tax_paid_at_lower_rate = 0.0; $tax_paid_at_higher_rate = 0.0; // Determine amount of income over 20000 and tax it at the higher rate if ( $salary > 20000 ) { $salary_taxable_at_higher_rate = $salary - 20000; $tax_paid_at_higher_rate = $salary_taxable_at_higher_rate * 0.2; } // Tax the rest at the lower rate $tax_paid_at_lower_rate = $salary * 0.05; echo "<table>"; echo "<tr><th>Tax paid at lower rate</td><td>{$tax_paid_at_lower_rate}</td></tr>"; echo "<tr><td>Tax paid at higher rate</td><td>{$tax_paid_at_higher_rate}</td></tr>"; echo "</table>";