为什么我的刷新CAPTCHA在Firefox中不起作用？ [重复]

This question already has an answer here:

这个问题在这里已有答案：

Refresh image with a new one at the same url 16 answers
使用相同的网址刷新图像16个答案

i use smarty with codeigniter. my refresh captcha work in chrome correctly and change picture of captcha but it doesn't work in firefox and my captcha doesn't change.

我使用smarty与codeigniter。我的刷新验证码正确地在chrome中工作并更改验证码的图片，但它在Firefox中不起作用，我的验证码不会改变。

part of my view:

我的观点的一部分：

<script>
function refreshCaptcha() {
$("#captcha_code").attr('src','{$url}Login/captcha');
}
</script>   
</head>
  <form class="m-t" role="form" action="{$url}admin/Dashboard" 
   method="POST">
     <img id="captcha_code" src="{$url}Login/captcha" />
    <a name="submit"  class="btnRefresh" onClick="refreshCaptcha();">Refresh 
  Captcha</a>
  </form>

my controller:

我的控制器：

   public function captcha()
   {        
    $image = @imagecreatetruecolor(120, 30) or die("Cannot Initialize new GD 
   image stream");
    $background = imagecolorallocate($image, 0xFF, 0xFF, 0xFF);
    imagefill($image, 0, 0, $background);
    $linecolor = imagecolorallocate($image, 0xCC, 0xCC, 0xCC);
    $textcolor = imagecolorallocate($image, 0x33, 0x33, 0x33);
    for($i=0; $i < 6; $i++)
    {  imagesetthickness($image, rand(1,3));
        imageline($image, 0, rand(0,30), 120, rand(0,30), $linecolor);}
    session_start();
    $digit = '';
    for($x = 15; $x <= 75; $x += 20)
    {   $digit .= ($num = rand(0, 9));          
        imagechar($image, rand(3, 5), $x, rand(2, 14), $num, $textcolor);
    $_SESSION['captcha_code'] = $digit;
    header('Content-type: image/png');
    imagepng($image);
    imagedestroy($image);
        }

1 个解决方案

#1

The img src attribute is the same, so it may not refresh correctly or the browser using cache (I'm not sure that only Firefox won't refresh).

img src属性是相同的，因此它可能无法正确刷新或浏览器使用缓存（我不确定只有Firefox不会刷新）。

I recommend you to add some parameter to prevent cache, such as time to url

我建议你添加一些参数以防止缓存，例如url的时间

<script>
function refreshCaptcha() {
   $("#captcha_code").attr('src','{$url}Login/captcha?_t='+new Date().getTime());
}
</script>

#1