The main differences between PHP and Flutter functions are declaration, syntax and return type. PHP functions use implicit return type conversion, while Flutter functions explicitly specify return types; PHP functions can specify optional parameters through ?, while Flutter functions use required and [] to specify required and optional parameters; PHP functions use = to pass naming Parameters, while Flutter functions use {} to specify named parameters.
PHP functions
function sum($a, $b) { return $a + $b; }
Flutter function
int sum(int a, int b) => a + b;
PHP function
function
Yes Specify optional parameters via ?
and set default values via =
. Named parameters are passed using =
.
function sum($a, $b = 0) { return $a + $b; } sum(1); // 1 sum(1, 2); // 3
Flutter function
Flutter function uses required
to specify required parameters, []
to specify optional parameters,{}
Specify named parameters.
int sum(int a, {int b = 0}) => a + b; sum(1); // 1 sum(1, 2); // 3
PHP function
PHP function uses implicit return type conversion and returns null
by default.
function add(int $a, int $b) { return $a + $b; // 返回 int 型 }
Flutter function
Flutter function explicitly specifies the return type.
int sum(int a, int b) => a + b;
PHP
<?php function get_username($id) { $db = connect_database(); $result = $db->query("SELECT username FROM users WHERE id='$id'"); if ($result->num_rows > 0) { return $result->fetch_assoc()['username']; } else { return null; } } $username = get_username(1); echo $username; // "john" ?>
Flutter
String? getUsername(int id) { // 连接数据库并查询数据... // 实际实现省略 // 假设返回的用户名为 "john" return "john"; } void main() { String? username = getUsername(1); print(username); // "john" }
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