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HomeBackend DevelopmentPHP Tutorial关于引用变量的疑惑

$foo='Bob';
$bar=&$foo;
$bar="my name is $bar";
echo $bar.'
';
echo $foo;

这是手册上的一个例子,我有疑惑的就是输出$bar的结果我能理解,但是为何输出$foo的时候,他的值不是Bob,而是my name is Bob,为何其值会变,请高手解释,谢谢!


回复讨论(解决方案)

这就是赋值和引用的区别
$foo='Bob';
$bar=&$foo; //$bar 和 $foo 指向了同一个变量表项
所以对 $bar 的任何改变,都会引起 $foo 的改变(除了删除)

就好比一个人有两个名字一样

这就是赋值和引用的区别
$foo='Bob';
$bar=&$foo; //$bar 和 $foo 指向了同一个变量表项
所以对 $bar 的任何改变,都会引起 $foo 的改变(除了删除)

就好比一个人有两个名字一样
也就是一旦引用,两个变量都一样了,是吧?

是的,两个变量的值都一样了

是的,两个变量的值都一样了
谢谢!

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