我有一个占位符图像,内容如下:
Your rating is:
[rating here]
我的 PHP 代码应该在占位符图像上留有空白的地方动态插入评分数字。我该怎么做?
最佳答案
这是一个如何做到这一点的例子 - 使用 gd function调用来制作您的图像,但播放得很好并缓存图像。这个示例通过确保如果浏览器已经有所需的图像,它返回 304...
来播放甚至更好#here's where we'll store the cached images
$cachedir=$_SERVER['DOCUMENT_ROOT'].'/imgcache/'
#get the score and sanitize it
$score=$_GET['score'];
if (preg_match('/^[0-9]\.[0-9]{1,2}$/', $score)
{
#figure out filename of cached file
$file=$cachedir.'score'.$score.'gif';
#regenerate cached image
if (!file_exists($file))
{
#generate image - this is lifted straight from the php
#manual, you'll need to work out how to make your
#image, but this will get you started
#load a background image
$im = imagecreatefrompng("images/button1.png");
#allocate color for the text
$orange = imagecolorallocate($im, 220, 210, 60);
#attempt to centralise the text
$px = (imagesx($im) - 7.5 * strlen($score)) / 2;
imagestring($im, 3, $px, 9, $score, $orange);
#save to cache
imagegif($im, $file);
imagedestroy($im);
}
#return image to browser, but return a 304 if they already have it
$mtime=filemtime($file);
$headers = apache_request_headers();
if (isset($headers['If-Modified-Since']) &&
(strtotime($headers['If-Modified-Since']) >= $mtime))
{
// Client's cache IS current, so we just respond '304 Not Modified'.
header('Last-Modified: '.gmdate('D, d M Y H:i:s', $mtime).' GMT', true, 304);
exit;
}
header('Content-Type:image/gif');
header('Content-Length: '.filesize($file));
header('Last-Modified: '.gmdate('D, d M Y H:i:s', $mtime).' GMT');
readfile($file);
}
else
{
header("HTTP/1.0 401 Invalid score requested");
}
如果你把它放在 image.php 中,你将在图像标签中使用如下内容
<img src="image.php?score=5.5" alt="5.5" />
关于php - 如何动态创建带有指定编号的图像?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/449858/