在PHP中添加多个变量的总和

Question

ok

so I have been stuck on this problem for a while and I'm sure there is a more elegant way of doing it.

I have 3 columns in a database -

Stand1 | Stand2 | Stand3

each column will either have a stand number (ie D30) or 'Not Assigned'

What I need to do is count how many stands have been assigned to that customer.

For example :

D30 | not assigned | not assigned would = 1

D30 | B30 | E30 = 3

The code I have so far is

if ($row["stand1"] == 'Not Assigned') {
    $stand1 = '0';
}  
else {
    $stand1 = '1';
}

if ($row["stand2"] == 'Not Assigned') {
    $stand2 = '0';
}  
else {
    $stand2 = '1';
}

if ($row["stand3"] == 'Not Assigned') {
    $stand3 = '0';
}  
else {
    $stand3 = '1';
}

I then thought I could try and count how many stand were assigned :

$standcount = $stand1 + $stand2 + $stand3

But when I print this out (everything else is in an array so loops through every customer) all I get is the total 3 for every customer.

I tried saving the data into an array like:

$standcount = array($stand1, $stand2, $stand3); 

But I get the same result. I thought a foreach loop may work but not sure how to do it.

Answer 1

I would suggest you to:

1. Set the columns' default value to NULL , so that if no value is provided in an entry you'll have a null value instead of a string (that can contains different letters, as in your case). After that you can simply perform the isset() check against each value.

2. Use a function to avoid code repetition (the main source of errors), something like:

    function check($value) { return (isset($value)) ? 1 : 0; } $stand_1 = check($row["stand1"]); $stand_2 = check($row["stand2"]); $stand_3 = check($row["stand3"]); 

If you instead want to use a string as "Not Assigned" or "NA", you can perform a case-insensitive check with strcasecmp() between the strings in case, for any reason, a value contains an extra space or a lower-case letter. In this case the check function would be:

function check($str) {
    return (strcasecmp($str, "NA") == 0) ? 0 : 1;
}
$stand_1 = check($row["stand1"]);
$stand_2 = check($row["stand2"]);
$stand_3 = check($row["stand3"]);