javascript - echo json_encode($array) 传递了之前的 echo

Question

我不了解 jQuery，所以如果这是一个愚蠢的问题，我很抱歉。

当我将值从 php 传递到 javascript 时，即使之前用 echo 打印的消息也被传递，我怎样才能避免这种情况？

php

  $Connection = new Connection("...");
  $array = $Connection->arrCol("SELECT IT FROM global", "IT");
  echo json_encode($array);

jQuery

$(document).ready(function(){
$("button").click(function(){
    $.get("services/test.php", function(data, status){
        alert("Data: " + data + "\nStatus: " + status);
    });
});
 });

结果

CONNECTED at (localhost) (user: root) (db: ...) stausUptime: 440790 Threads: 1 Questions: 1244 Slow queries: 0 Opens: 53 Flush tables: 1 Open tables: 1 Queries per second avg: 0.2 (message "echoed" by method of Connection in php)

["..."] (requested data)

Answer 1

如果您的 Connection 类执行回显，并且您不希望将其混合到 JSON 输出中，则必须控制输出缓冲区。

例如:

// Start catching the output
ob_start();

// Run code that echoes unwanted stuff under the hood
$Connection = new Connection("...");
$array = $Connection->arrCol("SELECT IT FROM global", "IT");

// Clear the output buffer and stop buffering (i.e. discard that echo)
ob_end_clean();

// Output JSON
header('Content-Type: application/json');
echo json_encode($array);