php - 图像无法显示，因为它包含错误，当我删除以下行时显示文本 "header(' Content-type : ' ...."

Question

当我试图从我的开发环境中的数据库加载图像时，无法加载图像，而是返回错误消息“无法显示图像，因为它包含错误。”

<?php

require_once 'app_config.php';                 //app config file
require_once 'database_connection.php';        //database connection

try{
//Get the image id.
if(!isset($_REQUEST['image_id'])){
handle_error("No image to load was specified.");
}
$image_id = $_REQUEST['image_id'];

//Build the SELECT statement
$select_query = sprintf("SELECT * FROM images WHERE image_id = %d", $image_id);

//Run the query
$result = mysql_query($select_query);

//Get the result and handle errors from getting no result
if(mysql_num_rows($result) == 0){
  handle_error("We couldn't find the requested image.", "No image found with and    ID of " . $image_id . ".");
 }
 $image = mysql_fetch_array($result);

//Tell the browser what's coming with headers
header('Content-type: ' . $image['mime_type']);
header('Content-length: ' . $image['file_size']);

echo $image['image_data']; 
}catch(Exception $exc){
  handle_error("Something went wrong loading your image.",
             "Error loading image: " . $exc->getMessage());
}

?>

Answer 1

存储图像数据时如何对其进行编码？我建议您尝试 base64_decode() 它，因为这是传输/存储图像数据的常见方式。

echo base64_decode($image['image_data']);
exit;