Questions about the PHP reference address changing the value of the variable

$foo = ' Bob '; Assign ' Bob ' to $foo $bar = & $foo; by $bar Reference $foo echo $foo. ' '; $bar = "My name is $bar"; modifying $bar variables echo $bar. ' '; echo $foo. ' '; The value of the $foo is also modified ?> Copy Code Output: bobmy name is bobmy name is Bob You can see that the original value has been modified, it occurs after the reference and is assigned, but the original variable is not changed until the value is assigned. Articles you may be interested in: A detailed introduction to PHP reference values through an instance to understand the difference between the value and the reference in PHP by example, see the efficiency of PHP address reference in PHP reference, "&" explanation

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