将函数更改为 PDO

这是我的api中使用的语句。这是第二个$result下面整个函数中的变量。如何将其更改为使用 PDO？

$result = query("SELECT p.IdPhoto, p.device_token, /*title,*/ p.IdUser FROM photos p JOIN login l ON (l.IdUser = p.IdUser) WHERE p.IdPhoto='%d'", $IdPhoto) ;

功能齐全

function stream($IdPhoto=0) {

if ($IdPhoto==0) {

   //Load Photos    
    $result = query("SELECT IdPhoto, device_token, /*title,*/ IdUser FROM photos /*p*/ ORDER BY IdPhoto DESC LIMIT 300 ");

} else {

    //Want this to be PDO :)
    $result = query("SELECT p.IdPhoto, p.device_token, /*title,*/ p.IdUser FROM photos p JOIN login l ON (l.IdUser = p.IdUser) WHERE p.IdPhoto='%d'", $IdPhoto) ;

}

这段代码可以代替第二个结果变量吗？我的目标是将其更改为 PDO，以便它可以更成功地扩展。到目前为止，还没有输出。

$dbh = new PDO('mysql:host=localhost;dbname=pushchat', 'pushchat', 'A very secure password!!!');    
    $result = $dbh->query("SELECT p.IdPhoto, p.device_token, /*title,*/ p.IdUser FROM photos p JOIN login l ON (l.IdUser = p.IdUser) WHERE p.IdPhoto='%d'", $IdPhoto) ;

这些是我的数据库连接值

'host'     => 'localhost',
'dbname'   => 'pushchat',
'username' => 'pushchat',
'password' => 'A very secure password!!!',

UpdatePHP日志文件

[08-Apr-2016 03:39:25 Europe/Berlin] PHP Notice:  Undefined index: IdPhoto in /Applications/MAMP/htdocs/Hi2/index.php on line 44

Update

在测试文件中使用 PDO 语法，浏览器返回一行。我怎样才能让应用程序现在通过 j son 调用它？

<?php  
$conn = new PDO('mysql:host=localhost;dbname=pushchat', 'pushchat', 'd]682\#%yI1nb3');

function new_function()

{
echo "hi<br>";

$an_int = 12;    

// If this is an integer

if (is_int($an_int)) 

{

global $conn;

$stmt = $conn->prepare("SELECT IdPhoto, device_token, IdUser FROM photos ORDER BY IdPhoto DESC LIMIT 300 ");

$stmt->execute();

$result = $stmt->fetch(PDO::FETCH_ASSOC);

print_r($result);

$swag_Bag = 'p.device_token';

    print_r($swag_Bag);

}

}
new_function();

 ?>

Update

这就是应用程序调用原来的方式stream功能。

-(void)refreshStream
{
//The "stream" command from the web API
[[API sharedInstance] commandWithParams:[NSMutableDictionary dictionaryWithObjectsAndKeys:@"stream", @"command", nil] onCompletion:^(NSDictionary *json)
{
    //got stream
    [self showStream:[json objectForKey:@"result"]];

    ...

    }];
}

尝试这个：

$conn = new PDO('mysql:host=localhost;dbname=dbname', 'root', 'password');
function stream($IdPhoto=0) {
global $conn;

if ($IdPhoto==0) {

    // load the last 300 photos
    $stmt = $conn->prepare("SELECT IdPhoto, device_token, IdUser FROM photos ORDER BY IdPhoto DESC LIMIT 300 ");
    $stmt->execute();
    $result = $stmt->fetch(PDO::FETCH_ASSOC);

} else {

//This is the statement i need to call explicitly via PDO

    //do the same as above, but just for the photo with the given id
    $stmt = $conn->prepare("SELECT p.IdPhoto, p.device_token, p.IdUser FROM photos p JOIN login l ON (l.IdUser = p.IdUser) WHERE p.IdPhoto= :idphoto ");
    $stmt->execute([':idphoto' => $IdPhoto]);
    $result = $stmt->fetch(PDO::FETCH_ASSOC);

}

if (!$stmt->errorInfo()[0]) {
    // if no error occured, print out the JSON data of the 
    // fetched photo data
    print json_encode($result);
} else {
    //there was an error, print out to the iPhone app
    errorJson('Photo stream is broken');
}
}