Thanks Tutorial！
<?phpdeclare(strict_types=1); // 为了严格明确传入参数的类型，可以每个文件前都加上function func1($name){ // function with parameterreturn "Hello " . $name . "!";
}echo func1("Alice");function func2($name = "nothing came in"){ // run with default parameterreturn "Hello " . $name . "!";
}echo "<br>";
echo func2();function func3(string $name) { // function with type-hinted parameter // recommandedreturn "Hello " . $name . "!";
}function func3_1(string $name) : bool { // 明确表示返回值类型的函数if (empty($name)) {return true;}else { return false;}
}function func3_2(bool|object $hm2ns) {// 明确严格类型模式后，可以这样写允许可能传入的不同类型参数，例如配合 pdo->fetch 使用
}is_bool(); // 这么判断类型echo "<br>";
// echo func3(1); // this will cause a TypeError due to strict_types=1
echo "<br>"; // scope of variables in functions$globalVar = "Benjamin";function func4() {// return "Hello " . $globalVar . "!"; //!! different from cpp , it cannot access $globalVar directlyglobal $globalVar; // need this first$result = "Hello " . $globalVar . "!"; // then ok to access from now on// cannot unset the global variable access without removing this variableglobal $result; //// return $result . $globalVar; // now $globalVar is undefined herereturn $result;
}echo func4();
echo "<br>";
echo $globalVar; function func5() {static $count = 0; // static variable inside function$count++;return $count;
}
// each time func5 is called, $count keeps its value before.
echo "<br>";
echo func5(); // 1
echo func5(); // 2
echo func5(); // 3
echo "<br>";define("PI",3.14); // define constant
// no $ before constant name
//use capitial letters for constant names by conventionfunction func6() {return PI; // 常量可以被直接访问
}$name = "dingFei";
for ($i = 0,$j = 0; $i < strlen($name); $i++){echo $name[$i] . " ";
}echo "<br>";while ($j < strlen($name)){echo $name[$j] . " ";$j++;
}echo "<br>";$j = 0;
do {global $j;echo $name[$j] . " ";$j++;
} while ($j < strlen($name));
unset($j); // remove global $jecho "<br>";$fruits = array("apple", "banana", "cherry");foreach ($fruits as $fruit){ // 遍历一个数组的简洁写法echo $fruit . " ";echo "<br>";
}
/*for (v: vec){cout<<i<<" ";} // 老朋友
*/ $dingFei = ["father" => "dingFei","son" => "DXJ","wife" => "for sure not apple",
];// associative arrayforeach ($dingFei as $name){ // 只会输出值echo $name . " ";echo "<br>";
}foreach ($dingFei as $relation => $name){ // 键和值echo $relation . ": " . $name . " ";echo "<br>";
}
