PHP 中 extract 同名覆盖


EXTR_OVERWRITE If there is a collision, overwrite the existing variable.

EXTR_SKIP If there is a collision, don’t overwrite the existing variable.

EXTR_PREFIX_SAME If there is a collision, prefix the variable name with prefix.

EXTR_PREFIX_ALL Prefix all variable names with prefix.

EXTR_PREFIX_INVALID Only prefix invalid/numeric variable names with prefix.

EXTR_IF_EXISTS Only overwrite the variable if it already exists in the current symbol table, otherwise do nothing. This is useful for defining a list of valid variables and then extracting only those variables you have defined out of $_REQUEST, for example.

EXTR_PREFIX_IF_EXISTS Only create prefixed variable names if the non-prefixed version of the same variable exists in the current symbol table.

EXTR_REFS Extracts variables as references. This effectively means that the values of the imported variables are still referencing the values of the array parameter. You can use this flag on its own or combine it with any other flag by OR’ing the flags.

If flags is not specified, it is assumed to be EXTR_OVERWRITE.


        $name = "wangsijie";
        $person = array('name' => "lnmcc", 'age' => 100);
        extract($person, EXTR_PREFIX_ALL, "person");
        echo "Name: {$name}, Person Name: {$person_name}, Person Age: {$person_age}";