你看到这个破裂吗？ 任何问题？ 简单的php if elseif语句

Question

I'm a total PHP newb, so there is probably a better way of outputting a row's class based on different variables.

Is this bad, and if it is why is it?

    if ($variable1 > 0 && $variable2 != 2)  {
        echo "<tr class='variable1'>";
        }
        elseif ($variable2==2)
        {
         echo "<tr class='variable2'>";
        }
        else {
              echo "<tr>";
                 }

Answer 1

I would write it like this:

$class_name = '';
if (2 == $variable2)
{
    $class_name = 'variable2';
}
elseif ($variable1 > 0)
{
    $class_name = 'variable1';
}
echo '<tr class="' , $class_name , '">';

notice that on the equality test I use the constant before the variable.. this is a habit so that if I miss one equal it would result in an error that I would be forced to correct it instead of a "strange" behavior

another thing is that I give the initial value to $class_name and that will be the default one

also I use apostrophes instead of quotation marks because it is faster (because the way you did it php will parse the string for variables)

and the last thing is that I echo multiple string.. that's also faster than concatenating 3 strings (

echo '<tr class="' , $class_name , '">'; 

and not echo

'<tr class="' . $class_name . '">';

)