# Calculator help

So I’ve been teaching myself php little by little and I tried to make a calculator. Now, I got the calculations correct however when I enter the numbers and click submit it shows the sum, difference, product, and quotient. I want to know how to tell it to only show one if that is chosen.

Php Code:[php]<?php

if (\$_POST[‘submit_calc’ && ‘option1’]) {
\$a=\$_POST[‘1’];
\$b=\$_POST[‘2’];

``````	\$sum=\$a+\$b;
echo "Sum equals:".\$sum."<br />";
``````

}

if (\$_POST[‘submit_calc’ && ‘option2’]) {
\$a=\$_POST[‘1’];
\$b=\$_POST[‘2’];

``````	\$dif=\$a-\$b;
echo "Difference equals:".\$dif."<br />";
``````

}

if (\$_POST[‘submit_calc’ && ‘option3’]) {
\$a=\$_POST[‘1’];
\$b=\$_POST[‘2’];

``````	\$product=\$a*\$b;
echo "product equals:".\$product."<br />";
``````

}

if (\$_POST[‘submit_calc’ && ‘option4’]) {
\$a=\$_POST[‘1’];
\$b=\$_POST[‘2’];

``````	\$quotient=\$a/\$b;
echo "quotient equals:".\$quotient;
``````

}

?>[/php]

Try this using “Else if”. That way it will show one section, else if that is not the one selected, try the next one etc.

[php]<?php

if (\$_POST[‘submit_calc’ && ‘option1’]) {
\$a=\$_POST[‘1’];
\$b=\$_POST[‘2’];

``````	\$sum=\$a+\$b;
echo "Sum equals:".\$sum."<br />";
``````

}elseif (\$_POST[‘submit_calc’ && ‘option2’]) {
\$a=\$_POST[‘1’];
\$b=\$_POST[‘2’];

``````	\$dif=\$a-\$b;
echo "Difference equals:".\$dif."<br />";
``````

}elseif (\$_POST[‘submit_calc’ && ‘option3’]) {
\$a=\$_POST[‘1’];
\$b=\$_POST[‘2’];

``````	\$product=\$a*\$b;
echo "product equals:".\$product."<br />";
``````

}elseif (\$_POST[‘submit_calc’ && ‘option4’]) {
\$a=\$_POST[‘1’];
\$b=\$_POST[‘2’];

``````	\$quotient=\$a/\$b;
echo "quotient equals:".\$quotient;
``````

}?>[/php]

It already knows when the button is pushed, no need to asking it the same question over and over, same with giving it \$a and \$b every time, just put it once. You’re variables are listed wrong too in the if statements. if (\$_POST[‘submit_calc’ && ‘option3’]) { will give out an error message because in submit_calc you’re missing the last ] and after the && you’re missing the \$_POST[ at the beginning. What i put below should fix those errors.
[php]
if(isset(\$_POST[‘submit_calc’])) {
\$a=\$_POST[‘1’];
\$b=\$_POST[‘2’];
if(\$_POST[‘option1’]) {
\$sum=\$a+\$b;
echo “Sum equals:”.\$sum."
";
}
if (\$_POST[‘option2’]) {
\$dif=\$a-\$b;
echo “Difference equals:”.\$dif."
";
}
if (\$_POST[‘option3’]) {
\$product=\$a*\$b;
echo “product equals:”.\$product."
";
}
if (\$_POST[‘option4’]) {
\$quotient=\$a/\$b;
echo “quotient equals:”.\$quotient;
}
}
?>[/php]