关于数据类型综合实例
目的:熟悉PHP的数据类型
涉及的内容:
HTML基础:
1、HTML基本框架;
2、div、form、input、table、tr、 td 标签
CSS:
层叠样式表不多做介绍;
PHP:
1、 (已讲);
2、PHP方法(未讲,function篇单独讲述);
3、 (已讲);
4、 、 (已讲);
5、count()函数:返回数组中元素的数目;
6、strlen()函数:返回字符串长度;
7、gettype()函数:返回数据类型;
7、is_null、is_bool、is_array等判断函数。
实例:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<style>
#main{
margin-top: 20px;
display: flex;
align-items: center;
justify-content: center;
}
td{
min-width: 100px;
max-width: 400px;
text-align: center;
word-wrap:break-word;
word-break:break-word;
}
</style>
</head>
<body>
<div id="main">
<div>
<form action="" method="get">
<input type="text" name="data" placeholder="输入想要查询的数据">
<input type="submit" value="提交">
<span style="color: red">*</span>提交之后获取到的值均为string类型
</form>
<table border="1">
<caption>
<h1>查询数据</h1>
</caption>
<tr>
<th>完整显示</th>
<th>数据类型</th>
<th>数据长度</th>
<th>数据内容</th>
</tr>
<?php
function look_all($obj){
echo "<tr>";
echo "<td>";
var_dump($obj);
echo "</td>";
echo "<td>".gettype($obj)."</td>";
if(is_string($obj)){
echo "<td>".strlen($obj)."</td>";
echo "<td>".$obj."</td>";
}
elseif (is_null($obj)){
echo "<td></td>";
echo "<td></td>";
}
elseif (is_bool($obj)){
echo "<td></td>";
$flg = $obj ? "true" : " false ";
echo "<td>".$flg."</td>";
}
elseif (is_array($obj)){
echo "<td>包含元素".count($obj)."个</td>";
echo "<td>";
print_r($obj);
echo "</td>";
}
else{
$flg=(string) $obj;
echo "<td>".strlen($flg)."</td>";
echo "<td>".$obj."</td>";
}
echo "</tr>";
}
$obj1 = 987654321;
$obj2 = 123456.789;
$obj3 = "Lucifer";
$obj4 = null;
$obj5 = true;
$obj6 = false;
$obj7 = array("id"=>1, "name"=>"Lucifer","age"=>26,"college"=>"浙江大学");
$obj8 = array($obj1,$obj2,$obj3,$obj4,$obj5,$obj6,$obj7);
foreach ($obj8 as $obj){
look_all($obj);
}
//$_GET获取到的值均为string类型
if(isset($_GET["data"])){
$data = $_GET["data"];
if($data==""){
$data = null;
}
look_all($data);
}
?>
</table>
</div>
</div>
</body>
</html>
运行结果: