PHP's =& operator

这两个PHP语句是否做同样的事情？：

$o =& $thing;

$o = &$thing;

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Yes, they are both the exact same thing. They just take the reference of the object and reference it within the variable $o . Please note, thing should be variables.

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They're not the same thing, syntactically speaking. The operator is the atomic =& and this actually matters. For instance you can't use the =& operator in a ternary expression. Neither of the following are valid syntax:

$f = isset($field[0]) ? &$field[0] : &$field;
$f =& isset($field[0]) ? $field[0] : $field;

So instead you would use this:

isset($field[0]) ? $f =& $field[0] : $f =& $field;

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They both give an expected T_PAAMAYIM_NEKUDOTAYIM error.

If you meant $o = &$thing; then that assigns the reference of thing to o. Here's an example:

$thing = "foo";

$o = &$thing;

echo $o; // echos foo

$thing = "bar";

echo $o; // echos bar

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