使用elseif时，php chatbot回发有效负载不起作用

Question

I'm making a Facebook chatbot and try to use postback payload but it didn't work , I have also checked in my log.

Everything prints the right value but it didn't enter my else if block.

My Code

$sender = $input['entry'][0]['messaging'][0]['sender']['id'];
$message = $input['entry'][0]['messaging'][0]['message']['text'];
$message_to_reply = '';
$payload = $input['entry'][0]['messaging'][0]['postback']['payload'];
$fp = file_put_contents( 'request.log', date('Y-m-d H:i:s')."PAYLOAD = ".$payload, FILE_APPEND);

if (strpos($message, 'hi') != '') {
  $message_to_reply = 'hi';
  $jsonData = '{
    "recipient":{
      "id":"' . $sender . '"
    },
    "message":{
      "text":"'.$message_to_reply.'",
    },
  }';

} elseif(strpos($payload, 'test') != '') {
  $message_to_reply = 'PAYLOAD DIDNT WORK';
  $jsonData = '{
    "recipient":{
      "id":"' . $sender . '"
     },
    "message":{
      "text":"'.$message_to_reply.'",
    },
  }';

} else {
  $message_to_reply= 'CHOOSE MENU';
  $jsonData = '{
    "recipient":{
      "id":"'. $sender.'"
    },
    "message":{
      "attachment":{
        "type":"template",
        "payload":{
          "template_type":"button",
          "text":"'.$message_to_reply.'",
          "buttons":[
            {
              "type":"web_url",
              "url":"https://petersapparel.parseapp.com",
              "title":"PROMOTION"
            },
            {
              "type":"postback",
              "title":"test",
              "payload":"test"
            }
          ]
        }
      }
    }
  }';
}

My if and else block works fine but when I click on button test, I get value $payload = 'test' but I don't know why it didn't enter the elseif block.

Please help me on this.

Answer 1

You need to change your condition like this:

if (strpos($message, 'hi') !== false)

elseif(strpos($payload, 'test') !== false) // As 0th position is considered as '' in if condition which you are comparing.

Answer 2

I saw you commenting in another question. Maybe my answer solves your problem as well? It is not about detecting, but trigger the sending of a message containing a postback.

See here: Facebook Chatbot postback not working

In addition, make sure, you have postbacks checked in the webhook section of your app.

Cheers