如何在PHP中循环遍历带有数组的Json对象答案

【问题标题】：How to loop through an Json object with array in PHP如何在PHP中循环遍历带有数组的Json对象
【发布时间】：2020-03-24 03:53:30
【问题描述】：

我得到以下 JSON 格式的数据。

{"Students":
[{"ID":"600","datetime":"26-11-2019 04-32-31","age":"12"},
{"ID":"601","datetime":"26-11-2019 04-32-31","age":"13"},
{"ID":"602","datetime":"26-11-2019 04-32-31","age":"12"},
{"ID":"603","datetime":"26-11-2019 04-32-31","age":"14"}
]}

我想编写一个 PHP 脚本来在 MYSQL 中插入这些数据。

我不确定如何编写循环来遍历这些数据。

我尝试了以下代码，但它不起作用。

//encode the Json request.
$obj = json_decode($content);

foreach($obj as $key){
 // $email = $decode['RouteID'];

}

【问题讨论】：

你能转储$key

标签： php json loops foreach

【解决方案1】：

$json = '{"Students":
[{"ID":"600","datetime":"26-11-2019 04-32-31","age":"12"},
{"ID":"601","datetime":"26-11-2019 04-32-31","age":"13"},
{"ID":"602","datetime":"26-11-2019 04-32-31","age":"12"},
{"ID":"603","datetime":"26-11-2019 04-32-31","age":"14"}
]}';
//convert json to array
$array = json_decode($json, true);

//loop
foreach($array['Students'] as $key => $val){
 echo "$key = $val \n"; 
}

//or print whole array
print_r($array);

print_r 的结果会是这样的：

(
    [Students] => Array
        (
            [0] => Array
                (
                    [ID] => 600
                    [datetime] => 26-11-2019 04-32-31
                    [age] => 12
                )

            [1] => Array
                (
                    [ID] => 601
                    [datetime] => 26-11-2019 04-32-31
                    [age] => 13
                )

            [2] => Array
                (
                    [ID] => 602
                    [datetime] => 26-11-2019 04-32-31
                    [age] => 12
                )

            [3] => Array
                (
                    [ID] => 603
                    [datetime] => 26-11-2019 04-32-31
                    [age] => 14
                )

        )

)

【讨论】：

【解决方案2】：

// creating connection to mysql
$servername = "localhost";
$username = "username";
$password = "password";

try {
    $conn = new PDO("mysql:host=$servername;dbname=DatbaseName", $username, $password);
    // set the PDO error mode to exception
    $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
    echo "Connected successfully";
    }
catch(PDOException $e)
    {
    echo "Connection failed: " . $e->getMessage();
    }

$content = '{"Students":
[{"ID":"600","datetime":"26-11-2019 04-32-31","age":"12"},
{"ID":"601","datetime":"26-11-2019 04-32-31","age":"13"},
{"ID":"602","datetime":"26-11-2019 04-32-31","age":"12"},
{"ID":"603","datetime":"26-11-2019 04-32-31","age":"14"}
]}';
$data= json_decode($content);

foreach($data->Students as $student){

$sql = "INSERT INTO users (ID, datetime, age) VALUES (?,?,?)";
$conn->prepare($sql)->execute([$student->ID, $student->datetime, $student->age]);

}

【讨论】：

【解决方案3】：

要遍历对象并获取其成员，您可以尝试以下操作：

foreach($json as $obj){
   echo $obj->name;
   .....

}

使用$key 将不起作用！

【讨论】：

【解决方案4】：

下面是简单的工作示例代码：-

<?php
$jsonData = '{"Students": [{"ID":"600","datetime":"26-11-2019 04-32-31","age":"12"},{"ID":"601","datetime":"26-11-2019 04-32-31","age":"13"},{"ID":"602","datetime":"26-11-2019 04-32-31","age":"12"},{"ID":"603","datetime":"26-11-2019 04-32-31","age":"14"}]}';

$JD = json_decode($jsonData);

 // print_r($JD);

   foreach ($JD->Students as $key => $value) {
    echo $value->ID . ", " . $value->datetime . ", " . $value->age . "<br>";
    //print_r($value);
}



 ?>

【讨论】：

【解决方案5】：

$data = '{"Students":
[{"ID":"600","datetime":"26-11-2019 04-32-31","age":"12"},
{"ID":"601","datetime":"26-11-2019 04-32-31","age":"13"},
{"ID":"602","datetime":"26-11-2019 04-32-31","age":"12"},
{"ID":"603","datetime":"26-11-2019 04-32-31","age":"14"}
]}';

$r = json_decode($data);


foreach($r->Students as $key => $value)
{
  //inser query
  $q = 'INSERT INTO <table_name>('ID','datetime','age') VALUES($value->ID,$value->datetime,$value->age);

}

【讨论】：

【解决方案6】：

您可以将 JSON 数据转换为 object 或 array。
使用 php json_decode 函数来实现。

转换为对象

$data = '{"Students":
[{"ID":"600","datetime":"26-11-2019 04-32-31","age":"12"},
{"ID":"601","datetime":"26-11-2019 04-32-31","age":"13"},
{"ID":"602","datetime":"26-11-2019 04-32-31","age":"12"},
{"ID":"603","datetime":"26-11-2019 04-32-31","age":"14"}
]}';

$obj = json_decode($data);

foreach ($obj->Students as $key => $value) {
  echo $value->age;    
}

如果要将 JSON 数据转换为数组，请将第二个参数 (true) 设置为 json_decode。功能

$data = '{"Students":
    [{"ID":"600","datetime":"26-11-2019 04-32-31","age":"12"},
    {"ID":"601","datetime":"26-11-2019 04-32-31","age":"13"},
    {"ID":"602","datetime":"26-11-2019 04-32-31","age":"12"},
    {"ID":"603","datetime":"26-11-2019 04-32-31","age":"14"}
    ]}';

    $array = json_decode($data, true);

    foreach ($array['Students'] as $key) {
      echo $key['age'];    
    }

【讨论】：