Code example of method returning reference type in php

Reference ofphp (that is, adding the & symbol in front of a variable, function, object, etc.) //The most important thing is todelete the variable referenced by, but the referenced variable cannot be accessed. But the content is not destroyed. The meaning of reference in PHP is: different names access the same variable content.

This article mainly introduces the method of returningreferencetype in PHP,

        

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Run the above code once, and you will almost understand that using &getRef() will bind $colorRef to $color, which means that $colorRef and $colorvariablespoint to Same value. When you change one of the values, the other will also change.

If $color is anarray, the same is true. The above code will behavebehaviorthe same in any version of PHP4/5.

The problem arises when $color is anObject.

In PHP4, getCopy will still return a copied Object; &getRef() returns a reference.

PHP5 is a bit different,
The latest PHP5.2 behaves the same as PHP4, getCopy() returns copy, &getRef() returns reference.
But some PHP5 versions are slightly different here, such as PHP5.1.6, which shows that getCopy() and &getRef() are both references.

Here getCopy() and &getRef() are twoglobal functions. If they are placed in a class and become member functions of the class, it will be another story...

PS: Returning References will not improve performance, but sometimes it will reduce performance, so don't take it for granted to use this feature to "optimize" the program.

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