通过恢复PHP代码创建JSON字符串

Question

基本上我以一个JSON格式的字符串开头。此字符串的一个例子是：
[{"options":[{"valid":true,"content":"Answer"}],"content":"Question1","type":"text"},{"options":[{"valid":false,"content":"Answer"}],"content":"Question2","type":"radios"}]

随着json_decode我将它转换成一个数组，看起来像这样在这个例子：

Array 
(
    [0] => stdClass Object 
     (
      [options] => Array 
       (
        [0] => stdClass Object 
         (
          [valid] => 1 
          [content] => Answer 
         ) 

       ) 

      [content] => Question1 
      [type] => text 
     ) 

    [1] => stdClass Object 
     (
      [options] => Array 
       (
        [0] => stdClass Object 
         (
          [valid] => 
          [content] => Answer 
         ) 

       ) 

      [content] => Question2 
      [type] => radios 
     ) 

) 

并使用该PHP代码存放在MySQL这样的：

$questions = json_decode($_POST['test']); 

     $con=mysqli_connect("Localhost","root","","test"); 

     if (mysqli_connect_errno()) 
     { 
      echo "Failed to connect to MySQL: " . mysqli_connect_error(); 
     } 

     foreach($questions as $question){ 
      $options = $question->options; 
      $options_id = array(); 
      $question_query = "INSERT INTO `question` (Content, Type) VALUES ('{$question->content}', '{$question->type}')"; 
      echo $question_query; 
      if(!mysqli_query($con, $question_query)){ echo mysqli_error($con);} 
      $question_id= mysqli_insert_id($con); 
      echo $question_id; 
      foreach($options as $option){ 
      $options_query = "INSERT INTO `option` (Question_id, Content) VALUES ({$question_id}, '{$option->content}')"; 
      echo $options_query; 
      if(!mysqli_query($con, $options_query)){ 
      echo mysqli_error($con); 
     } 
    } 

这只是存储问题，这是可能的答案。

因此，在某些时候我需要这个过程向后（从MySQL获取信息并再次构建JSON，以便呈现相应的UI）。有没有一种方法可以恢复这些代码，并使这个过程向后？也许与json_enconde？

Answer 1

你看起来像下面

$a = '[{"options":[{"valid":true,"content":"Answer"}],"content":"Question1","type":"text"},{"options":[{"valid":false,"content":"Answer"}],"content":"Question2","type":"radios"}]' ; 
$b = json_decode($a,true); 
//print_r($b); 

foreach($b as $key=>$val){ 
    echo 'Content : '.$val['content']; 
    echo '<br />'; 
    echo 'Type : '.$val['type']; 
    echo '<br />'; 
    foreach($val['options'] as $key1=>$val1){ 
     echo 'Valid :'.$val1['valid']; 
     echo '<br />'; 
     echo 'Answer : '.$val1['content']; 
     echo '<br />'; 

    } 
    echo '<hr><br />'; 
} 

输出看起来像

Content : Question1 
Type : text 
Valid :1 
Answer : Answer 
------------------------------------------------------ 
Content : Question2 
Type : radios 
Valid : 
Answer : Answer