<?php?>、echo
php相關代碼都要寫在php和後面的？之間
echo：就是向網頁中輸出字元串
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>PHP頁面</title>
</head>
<body>
<div>PHP to hello world</div>
<?php
// 所有的php代碼都要寫在這裡
// echo 就是向網頁輸出字元串
/*
段注釋
*/
echo "<div>這裡是一個最簡單的php動态網站</div>";
?>
</body>
</html>
變量及區分單雙引号
php變量由$符号開始，後跟變量名。
變量名由字母數字下劃線組成，不能以數字開頭，區分大小寫
字元串由點連接配接
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>PHP頁面</title>
</head>
<body>
<div>PHP to hello world</div>
<?php
$num = 123;
// php中單引号和雙引号不同
echo "<div>變量值為:$num</div>";//變量輸出是123
echo '<div>變量值為:$num</div>';//變量輸出是$num
// 字元串的拼接，php由點連接配接，JavaScript由+連接配接
echo "<div>變量值為:".$num."</div>";
?>
</body>
</html>
建立數組、echo、print_r()、var_dump()差別
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>PHP頁面</title>
</head>
<body>
<div>測試頁面</div>
<?php
// 建立數組
$arr=array(1,2,3,4);
$arr1 =array("name","yes");
$arr2 =array("key"=>"value","word"=>"yes");
// echo $arr;-//輸出報錯
echo $arr[0]; //1
echo "\n"; // 不識别\n換行
echo $arr[1];
echo "<br>"; //換行
echo $arr[2];
echo "<br>";
print_r($arr1);//Array ( [0] => name [1] => yes )
echo "<br>";
var_dump($arr2);//比print_r()列印詳細點
?>
</body>
</html>
二維數組
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>PHP頁面</title>
</head>
<body>
<div>測試頁面</div>
<?php
// 建立二維數組
$arr =array();
$arr[0] =array(1,2,3);
$arr[1]=array(4,5,6);
$arr[2]=array(7,8,9);
print_r($arr);
// Array ( [0] => Array ( [0] => 1 [1] => 2 [2] => 3 )
// [1] => Array ( [0] => 4 [1] => 5 [2] => 6 )
// [2] => Array ( [0] => 7 [1] => 8 [2] => 9 )
// )
$arr1 =array(10);
$arr1["house1"] =array("area"=>234,"room"=>4);
$arr1["house2"] =array("area"=>334,"room"=>6);
echo "<br>";
print_r($arr1);
// Array ( [0] => 10 [house1] => Array ( [area] => 234 [room] => 4 )
// [house2] => Array ( [area] => 334 [room] => 6 ) )
?>
</body>
</html>
常見資料類型及調用函數
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>PHP頁面</title>
</head>
<body>
<div>測試頁面</div>
<?php
$arr =array(1,2,3,4);
//gettype()函數
echo "<br>";
echo gettype($arr);//array
$num =23;
echo "<br>";
echo gettype($num);//integer
$num =23.3;
echo "<br>";
echo gettype($num);//double
$bool =true;
echo "<br>";
echo gettype($bool);//boolean
echo "<br>";
//for循環,count計算數組長度
for($i=0;$i<count($arr);$i++){
print_r($arr[$i]);
}
echo "<br>";
//foreach周遊
foreach ($arr as $key => $value) {
echo $key."--->".$value."<br>";
}
?>
</body>
</html>
自定義函數
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>PHP頁面</title>
</head>
<body>
<div>測試頁面</div>
<?php
// 自定義函數,函數名不區分大小寫，與js的不同
$res=FunName(13,3);//先調用不受影響，與js類似
echo $res;
echo "<br>";
function funName($num,$num1){
return $num+$num1;
}
$res=funName(23,3);
echo $res;
echo "<br>";
//系統函數，将數組變為json資料
// $arr =array(1,2,3);//[1,2,3]
$arr =array("key"=>"23","sum"=>"ouver");//{"key":"23","sum":"ouver"}
$json =json_encode($arr);
echo $json;
?>
</body>
</html>
http協定常用請求方式及在php中的用法
- get 用來從伺服器擷取資料（擷取的參數一般用來查詢）
- post 添加資料
- put 修改資料
- delete 删除資料
<?php
/*
擷取從網頁擷取的資料，?連接配接
http://jditems.com/php/page.php?flag=3
*/
$var=$_GET['flag'];
echo "<p>$var</p>";
?>
post小用例
目錄：
page.php
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>PHP頁面</title>
</head>
<body>
<div>測試頁面</div>
<div>
<!-- form預設method為get -->
<form action="page2.php" method="post">
使用者名：<input type="text" name="username"><br>
密 碼：<input type="password" name="pw"><br>
<input type="submit" value="送出">
</form>
</div>
</body>
</html>
paga2.php
網頁和伺服器簡單互動案例
根據學号查詢成績
page.php
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>PHP頁面</title>
</head>
<body>
<div>測試頁面</div>
<div>
<!-- form預設method為get -->
<form action="page2.php" method="post">
學 号：<input type="text" name="id"><br>
<input type="submit" value="送出">
</form>
</div>
</body>
</html>
page2.php
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>背景</title>
</head>
<body>
<?php
// 相當于背景
$arr =array();
$arr['100'] =array("name"=>"小紅","chinese"=>"120","math"=>"120","english"=>"134");
$arr['102'] =array("name"=>"小名","chinese"=>"124","math"=>"70","english"=>"124");
$arr['112'] =array("name"=>"小東","chinese"=>"110","math"=>"130","english"=>"90");
$id =$_POST['id'];
$score = $arr[$id];
echo "<ul><li>姓名：$score[name]</li><li>國文：$score[chinese]</li><li>數學：$score[math]</li><li>英語：$score[english]</li></ul>";
?>
</body>
</html>