What does this symbol mean “?->” in php, within an object or null value [duplicate]

问题

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Reference — What does this symbol mean in PHP? (20 answers)

Closed 24 days ago.

Could you please explain what does the operator ?-> do in PHP, since I have this piece of code:

$drive = $objDrive?->func?->getDriver()?->value;

回答1:

For the moment, it's just a proposal, you can find it enter link description here. It's the NullSafe Operator, it returns null in case you try to invoke functions or get values from null... Example

$objDrive = null;
$drive = $objDrive?->func?->getDriver()?->value; //return null
$drive = $objDrive->func->getDriver()->value; // Error: Trying to get property 'func' of non-object

来源：https://stackoverflow.com/questions/62178354/what-does-this-symbol-mean-in-php-within-an-object-or-null-value