php语法命名,我想看看它是否正确

Hey I've been reviewing over w3schools and I just want to check if my naming of syntax is right

if someone can check it or help me out

<?php

if (isset($_POST['name']) && isset($_POST['name2'])) {
    $num=$_POST['name'];
    $num2=$_POST['name2'];
    echo  $num . ' multiplyed by '. $num2 . ' = '.$num*$num2;
}

else{
    echo '';
}


?>

the if is a condition statement?

isset is function

$_POST[name] is inside the parameter and it is a global variable (question what exactly is the definition of a global variable)

$num and $num2 are variables

name and name2 are marks from the HTML name, but what is the correct definition of name and name2

no. - if in PHP it is called a construct. But many would argue it okay to call a conditional statement. A conditional statement is really the statement inside the if block. As you can see we actully have multiple statements.

if(condition) { // <- This is a if statement.
    statement // the statement is conditional.

yes - isset is a native php function

yes - $num and $num2 are variables. (if you do not know all types a variable can be in PHP, now would be a great time to learn.)

Lastly "name and name2 are marks from the HTML name, but what is the correct definition of name and name2" no - are called keys, array index or subscript. These provide a way to define which specific index in a array we are using.

$_POST is a native superglobal variable of the type array. A superglobal is accessable from all scopes. If you have not yet encountered what scopes are, no worries, you will as soon.