PHP函数表单不起作用

Question

Why is this php function not working? It does work when not using $element. With $element it always returns test.

function setVar($element)
 {
    if(isset($_POST['$element'])){
    $varname = $_POST['$element']; 
    } 
    else {
    $varname = 'test';
    }
    return $varname;
 }

 $var = setVar('element_6');

Answer 1

You probably mean:

... $_POST[$element] ...

without the quotes? Single-quoted content never gets replaced.