while(list($key,$value)=each($arr)) { echo $key."=>".$value; echo "<br>"; }
时间: 2024-05-24 12:11:40 浏览: 102
This code snippet loops through an array using the `each()` function which returns the current key/value pair and advances the array cursor to the next element. The `list()` function is used to assign the returned key/value pair to two separate variables: `$key` and `$value`. The loop then echoes out each key/value pair with a line break after each pair.
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<?php $arr = array( array( 'stu_no'=>2011211, 'name'=>'张三', 'age' =>18, 'gender'=>'男' 'height'=>'175cm', 'weight'=>'65kg', 'email'=>'admin@163.com', 'colege'=>'土木工程学院', ), array( 'stu_no'=>2011212, 'name'=>'李四', 'age' =>18, 'gender'=>'男' 'height'=>'168cm' 'weight' =>'55kg' 'email'=>'admin@163.com' 'colege'=>'体育学院' ), array( 'stu_no'=>2011213, 'name'=>'王五', 'age' =>19, 'gender'=>'男' 'height'=>'165cm' 'weight' =>'44kg' 'email'=>'admin@163.com' 'colege'=>'数学学院' ) ) ?> <!DOCTYPE html> <html> <head> </head> <body> <table > <tr> <th>学号</th> <th>姓名</th> <th>年龄</th> <th>性别</th> <th>身高</th> <th>体重</th> <th>邮箱</th> <th>学院</th> </tr> <?php foreach ($arr as $key => $value) {?> <tr> <td><?php echo $value['stu_no']; ?></td> <td><?php echo $value['name']; ?></td> <td><?php echo $value['age']; ?></td> <td><?php echo $value['gender']; ?></td> <td><?php echo $value['height']; ?></td> <td><?php echo $value['weight']; ?></td> <td><?php echo $value['email']; ?></td> <td><?php echo $value['colege']; ?></td> </tr> <?php } ?>
您好!这段代码是一个包含一个二维数组的PHP代码,该数组中包含了几个学生的信息,通过遍历数组,将学生的信息以表格的形式输出到HTML页面中。不过需要注意的是,代码中存在一些语法错误,可能会导致程序无法正常运行,例如:数组元素的末尾缺少了逗号,导致数组解析出错。以下是修改后的代码:
```php
<?php
$arr = array(
array(
'stu_no' => 2011211,
'name' => '张三',
'age' => 18,
'gender' => '男',
'height' => '175cm',
'weight' => '65kg',
'email' => 'admin@163.com',
'college' => '土木工程学院',
),
array(
'stu_no' => 2011212,
'name' => '李四',
'age' => 18,
'gender' => '男',
'height' => '168cm',
'weight' => '55kg',
'email' => 'admin@163.com',
'college' => '体育学院',
),
array(
'stu_no' => 2011213,
'name' => '王五',
'age' => 19,
'gender' => '男',
'height' => '165cm',
'weight' => '44kg',
'email' => 'admin@163.com',
'college' => '数学学院',
),
);
?>
<!DOCTYPE html>
<html>
<head>
<title>学生信息</title>
</head>
<body>
<table>
<tr>
<th>学号</th>
<th>姓名</th>
<th>年龄</th>
<th>性别</th>
<th>身高</th>
<th>体重</th>
<th>邮箱</th>
<th>学院</th>
</tr>
<?php foreach ($arr as $key => $value) { ?>
<tr>
<td><?php echo $value['stu_no']; ?></td>
<td><?php echo $value['name']; ?></td>
<td><?php echo $value['age']; ?></td>
<td><?php echo $value['gender']; ?></td>
<td><?php echo $value['height']; ?></td>
<td><?php echo $value['weight']; ?></td>
<td><?php echo $value['email']; ?></td>
<td><?php echo $value['college']; ?></td>
</tr>
<?php } ?>
</table>
</body>
</html>
```
希望对您有所帮助!
帮我把下边这块代码转成Java代码: private function query_arrtoxml($arr,$withRoot=true){ $xml =$withRoot?'<?xml version="1.0" encoding="utf-16" ?>':''; foreach ($arr as $key=>$val){ if(is_array($val)){ $xml.="<".$key.">".$this->query_arrtoxml($val,false)."</".$key.">"; }else{ $xml.="<".$key.">".$val."</".$key.">"; } } if($withRoot){ $xml.=""; } return $xml; }
以下是Java代码:
```
private String query_arrtoxml(Map<String, Object> arr, boolean withRoot) {
String xml = withRoot ? "<?xml version=\"1.0\" encoding=\"utf-16\" ?>" : "";
for (String key : arr.keySet()) {
Object val = arr.get(key);
if (val instanceof Map) {
xml += "<" + key + ">" + query_arrtoxml((Map<String, Object>) val, false) + "</" + key + ">";
} else {
xml += "<" + key + ">" + val + "</" + key + ">";
}
}
if (withRoot) {
xml += "";
}
return xml;
}
```
需要注意的是,Java中的Map对象需要用泛型来指定键值对的类型,所以我们将$arr改为了Map<String, Object>。此外,Java中的if语句需要用boolean类型来判断条件,所以我们将$is_withhead改为了withRoot,并将其类型改为了boolean。最后,Java中的字符串拼接需要使用+运算符,而不能像PHP中直接使用.运算符。