Question

您好我使用了聊天应用程序教程中的代码片段，其所有脚本都运行良好但是在我调整它以使代码根据我的要求工作之后几乎所有脚本都在工作，除了检索对话

我遇到的错误是它没有从我的数据库中检索对话

这是修改过的脚本

 //Create the JSON response.
$json = '{"messages": {';
//Check to ensure the user is in a chat room.
if(!isset($_GET['chat'])) {

    $json .= '"message":[ {';
    $json .= '"id":  "0",
                "user": "Admin",
                "text": "You are not currently in a chat session.  &lt;a href=""&gt;Enter a chat session here&lt;/a&gt;",
                "time": "' . date('h:i') . '"
            }]';
} else {
    $con3 = new PDO("mysql:host=". db_host .";dbname=db", db_username , db_password);
    $con3->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION );

    $con4 = new PDO("mysql:host=". db_host .";dbname=chat_db", db_username , db_password);
    $con4->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION );
    $sql5 = "SELECT * FROM users WHERE id = :rid LIMIT 1";
    $stmt6=$con4->prepare($sql5);
    $stmt6->bindValue( 'rid',$_POST['rid'], PDO::PARAM_STR);
    $stmt6->execute();
        foreach($stmt6->fetchAll()as $res)
            {
                $usern = $res['username'];
                $user_lvl = $res['ulvl'];
            }

    $comb = $usern . $_POST['name'];

      //Validation if msgid exists before creating a new table on the 2nd database
      $sql6="SELECT msgid FROM thread WHERE combination1=:msgids OR combination2=:submsgids LIMIT 1";
      $msg_id = $con4->prepare($sql6);
      $msg_id->bindParam(':msgids', $comb, PDO::PARAM_STR);
      $msg_id->bindParam(':submsgids', $comb, PDO::PARAM_STR);
      $msg_id->execute();
      $msgd = $msg_id->fetchColumn();
      $tbpre = $msgd . "chat_conversation";
    $sql7 = "SELECT msgid, message_content, username , message_time FROM $tblpre WHERE msgid=:chat";

    $stmt7=$con3->prepare($sql7);
    $stmt7->bindValue( ':chat', $msgd, PDO::PARAM_STR);
    $stmt7->execute();

    $message_query = $stmt7;
    //Loop through each message and create an XML message node for each.
    if(count($message_query) > 0) {
        $json .= '"message":[ ';    
        while($message_array = $stmt7->fetch(PDO::FETCH_ASSOC)) {
            $json .= '{';
            $json .= '"id":  "' . $message_array['msgid'] . '",
                        "user": "' . htmlspecialchars($message_array['username']) . '",
                        "text": "' . htmlspecialchars($message_array['message_content']) . '",
                        "time": "' . $message_array['message_time'] . '"
                    },';
        }
        $json .= ']';
    } else {
        //Send an empty message to avoid a Javascript error when we check for message lenght in the loop.
        $json .= '"message":[]';
    }

}

//Close our response

$json .= '}}';
echo $json;

以下是调用此脚本的代码

    //Gets the current messages from the server
        function getChatText() {
            if (receiveReq.readyState == 4 || receiveReq.readyState == 0) {
                receiveReq.open("GET", 'includes/getChat.php?chat='+uid+'&last=' + lastMessage, true);
                receiveReq.onreadystatechange = handleReceiveChat; 
                receiveReq.send(null);
            }           
        }
        function sendChatText() {

            if (sendReq.readyState == 4 || sendReq.readyState == 0) {
                sendReq.open("POST", 'includes/getChat.php?last=' + lastMessage, true);
                sendReq.setRequestHeader('Content-Type','application/x-www-form-urlencoded');
                sendReq.onreadystatechange = handleSendChat; 
                var param = 'message=' + document.getElementById('txtA').value;
                param += '&name='+user;
                param += '&uid='+uid;
                param += '&rid='+document.getElementById('trg').value;
                sendReq.send(param);
                document.getElementById('txtA').value = '';
            }                           
        }
    //When our message has been sent, update our page.
        function handleSendChat() {
            //Clear out the existing timer so we don't have 
            //multiple timer instances running.
            clearInterval(mTimer);
            getChatText();

        }
        function handleReceiveChat() {
            if (receiveReq.readyState == 4) {
                //Get a reference to our chat container div for easy access
                var chat_div = document.getElementById('clog');


                var response = eval("(" + receiveReq.responseText + ")");
                for(i=0;i < response.messages.message.length; i++) {
                    chat_div.innerHTML += response.messages.message[i].user;
                    chat_div.innerHTML += '&nbsp;&nbsp;<font class="chat_time">' +  response.messages.message[i].time + '</font><br />';
                    chat_div.innerHTML += response.messages.message[i].text + '<br />';
                    chat_div.scrollTop = chat_div.scrollHeight;
                    lastMessage = response.messages.message[i].id;
                }
                mTimer = setTimeout('getChatText();',20000); //Refresh our chat in 2 seconds
            }
        }

我在这里错过了什么或做错了吗？

Answer 1

您应该使用json_encode重写：

$messages = array();
//Check to ensure the user is in a chat room.
if(!isset($_GET['chat'])) {
    $message_object = (object) array(
        "id"=>"0",
        "user"=>"Admin",
        "text"=>"You are not currently in a chat session.  &lt;a href=\"\"&gt;Enter a chat session here&lt;/a&gt;",
        "time"=>date('h:i')
    );
    $messages[] = (object) array("message"=>$message_object);
} else {
    $con3 = new PDO("mysql:host=". db_host .";dbname=db", db_username , db_password);
    $con3->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION );

    $con4 = new PDO("mysql:host=". db_host .";dbname=chat_db", db_username , db_password);
    $con4->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION );
    $sql5 = "SELECT * FROM users WHERE id = :rid LIMIT 1";
    $stmt6=$con4->prepare($sql5);
    $stmt6->bindValue( 'rid',$_POST['rid'], PDO::PARAM_STR);
    $stmt6->execute();
        foreach($stmt6->fetchAll()as $res)
            {
                $usern = $res['username'];
                $user_lvl = $res['ulvl'];
            }

    $comb = $usern . $_POST['name'];

    //Validation if msgid exists before creating a new table on the 2nd database
    $sql6="SELECT msgid FROM thread WHERE combination1=:msgids OR combination2=:submsgids LIMIT 1";
    $msg_id = $con4->prepare($sql6);
    $msg_id->bindParam(':msgids', $comb, PDO::PARAM_STR);
    $msg_id->bindParam(':submsgids', $comb, PDO::PARAM_STR);
    $msg_id->execute();
    $msgd = $msg_id->fetchColumn();
    $tbpre = $msgd . "chat_conversation";
    $sql7 = "SELECT msgid, message_content, username , message_time FROM $tblpre WHERE msgid=:chat";

    $stmt7=$con3->prepare($sql7);
    $stmt7->bindValue( ':chat', $msgd, PDO::PARAM_STR);
    $stmt7->execute();

    $message_query = $stmt7;
    //Loop through each message and create an XML message node for each.
    if(count($message_query) > 0) {
        $message_object = (object) array(
            "id"=>$message_array['msgid'],
            "user"=>htmlspecialchars($message_array['username']),
            "text"=>htmlspecialchars($message_array['message_content']),
            "time"=>$message_array['message_time'
        );
        $messages[] = (object) array("message"=>$message_object);
    } else {
        //Send an empty message to avoid a Javascript error when we check for message lenght in the loop.
        $messages[] = (object) array("message"=>array());
    }

}

//Close our response
$result = (object) array('messages'=>$messages);
$json = json_encode($result);
echo $json;

检索JSON结果

1 个答案: