imagecreatefromgif

(PHP 3, PHP 4 )

imagecreatefromgif -- Create a new image from file or URL

Description

resource imagecreatefromgif ( string filename)

imagecreatefromgif() returns an image identifier representing the image obtained from the given filename.

imagecreatefromgif() returns an empty string on failure. It also outputs an error message, which unfortunately displays as a broken link in a browser. To ease debugging the following example will produce an error GIF:

例子 1. Example to handle an error during creation (courtesy vic@zymsys.com)

function LoadGif ($imgname) {
    $im = @imagecreatefromgif ($imgname); /* Attempt to open */
    if (!$im) { /* See if it failed */
        $im = imagecreate (150, 30); /* Create a blank image */
        $bgc = imagecolorallocate ($im, 255, 255, 255);
        $tc = imagecolorallocate ($im, 0, 0, 0);
        imagefilledrectangle ($im, 0, 0, 150, 30, $bgc);
        /* Output an errmsg */
        imagestring ($im, 1, 5, 5, "Error loading $imgname", $tc);
    }
    return $im;
}

注: Since all GIF support was removed from the GD library in version 1.6, this function is not available if you are using that version of the GD library.

提示: 如果 "fopen wrappers" 已经被激活,则您在使用该函数的时候,可以把 URL 作为文件名来使用。请参阅 fopen() 获取怎样指定文件名的详细信息以及支持的 URL 协议的列表 附录 I

警告

Windows 版本的 PHP 在 4.3.0 版之前不支持该函数的远程文件访问,即使 allow_url_fopen 选项已被激活。