Question

我有以下字符串：

{"Coords":[{"Accuracy":"65","Latitude":"53.277720488429026","Longitude":"-9.012038778269686","Timestamp":"Fri Jul 05 2013 11:59:34 GMT+0100 (IST)"},{"Accuracy":"65","Latitude":"53.277720488429026","Longitude":"-9.012038778269686","Timestamp":"Fri Jul 05 2013 11:59:34 GMT+0100 (IST)"},{"Accuracy":"65","Latitude":"53.27770755361785","Longitude":"-9.011979642121824","Timestamp":"Fri Jul 05 2013 12:02:09 GMT+0100 (IST)"},{"Accuracy":"65","Latitude":"53.27769091555766","Longitude":"-9.012051410095722","Timestamp":"Fri Jul 05 2013 12:02:17 GMT+0100 (IST)"},{"Accuracy":"65","Latitude":"53.27769091555766","Longitude":"-9.012051410095722","Timestamp":"Fri Jul 05 2013 12:02:17 GMT+0100 (IST)"}],"Scan":"Whatever"}

我想在php中解码。该字符串是通过SQL查询获得的。请参阅以下代码：

$TrackDetails_Query= "SELECT * FROM Tracks WHERE TrackID='".$TrackNum."' ORDER BY TrackID DESC";

        $TrackDetails_Result= mysql_query($TrackDetails_Query) or die (mysql_error());

        if (mysql_num_rows($TrackDetails_Result)==0){
                echo 'There are no tracks for the number entered';
            }
        else{
                            $traces=$row['Traces'];
                            $decoded_traces=json_decode($traces);
                            echo $decoded_traces;
            }
    }

但我收到错误：

Catchable fatal error: Object of class stdClass could not be converted to string

Answer 1

您收到错误是因为您试图将stdClass对象转换为字符串，这是它不支持的。

而不是echo $decoded_traces尝试var_dump($decoded_traces) - 这将提供您已解码的对象的诊断视图（我认为这是您想要的）。你会发现它看起来像这样

class stdClass#1 (2) {
  public $Coords =>
  array(5) {
    [0] =>
    class stdClass#2 (4) {
      public $Accuracy =>
      string(2) "65"
      public $Latitude =>
      string(18) "53.277720488429026"
      public $Longitude =>
      string(18) "-9.012038778269686"
      public $Timestamp =>
      string(39) "Fri Jul 05 2013 11:59:34 GMT+0100 (IST)"
    }
    [1] => (more of the same, edited for brevity)
    [2] =>
    [3] =>
    [4] =>
  }
  public $Scan =>
  string(8) "Whatever"
}

默认情况下，json_encode将创建如上所述的stdClass对象。如果您更喜欢关联数组，请将true作为第二个参数传递给json_decode，例如$decoded_traces=json_decode($traces, true);

另外，虽然stdClass不能变成字符串，但是你自己的类可以 - 实现__toString魔法的类可以转换为字符串！

Answer 2

使用json_encode($traces)这会将数组转换为字符串。 json_decode()用于将字符串转换为数组或对象数组

Answer 3

尝试使用此功能 $decoded_traces=json_decode($traces, true);

而不是这个 $decoded_traces=json_decode($traces);

它会将你的stdClass转换为数组。请注意，$decoded_traces是数组，然后您可以根据需要使用。

Answer 4

这是一个古老的问题，仍然可以回答那些像我一样遇到它的人。

尝试json_encode（$ traces）;

在我的情况下

return var_dump(json_encode($result[0]));

结果是：

string(34) "{"id":1,"content":"test database"}"

Answer 5

$decoded_traces是一个对象。你不能简单地echo一个对象，因为这没有意义。

如果要调试对象，请使用var_dump($decoded_traces)。

Answer 6

代替

 $decoded_traces=json_decode($traces);
 echo $decoded_traces;

尝试

$decoded_traces=json_decode($traces, true);
print_r $decoded_traces;

类stdClass的对象无法转换为字符串错误

6 个答案: