使用 PHP 的 if/else 语句？

Question

I am trying to do a survey and based on people's answers I want to return an answer. I am using PHP to use the If/Else statement, and I am very new to PHP. Since PHP is pretty similar to Javascript with the If/Else statements, besides the $ sign, I was attempted doing a function with a getelement.byid() inside of it, but seem to be getting a syntax error and can't figure out what that is. Here is the code:

<?php

function order()

{
if $doc->getElementById(ball) then 

    {print "you chose ball";
    }


}

?>

the error I get is in the if $doc->getElementById(ball) then line. This is a PHP page on its own that is called from an HTML page. I'm sure it's something minor, but does anyone have an idea on what's missing/wrong with that line?

Answer 1

This is just basic syntax. You don't have parentheses around the condition:

if (condition){
    //do something
}

if ($doc->getElementById(ball)){
    print "you chose ball";
}

Here's the documentation on the if statement

Answer 2

<?php
function order()
{
    if ($doc->getElementById(ball))
    {
        print "you chose ball";
    }
}
?>

Answer 3

There are several errors with your code, I will list them in comments:

<?php

function order()

{
    // Missing opening/closing parentheses (); no "then" in php.
    if ($doc->getElementById(ball))
    // Where are you referencing $doc from? Unlike javascript, php does not have built-in DOM manipulation.    
    {print "you chose ball";
    }


}

?>