php 上传时的唯一文件名

Question

我的网站上有一个上传图片的提交讨论表。现在，我想在用户提交图片时上传一个唯一的文件名，这样我就可以显示所有图片的结果并避免重复的文件名。

我如何用 php 做到这一点？如果您需要我的表单处理代码，我会上传它。

Answer 1

可以使用uniqid()函数生成唯一ID

/**
 * Generate a unique ID
 * @link http://www.php.net/manual/en/function.uniqid.php
 * @param prefix string[optional] <p>
 * Can be useful, for instance, if you generate identifiers
 * simultaneously on several hosts that might happen to generate the
 * identifier at the same microsecond.
 * </p>
 * <p>
 * With an empty prefix, the returned string will
 * be 13 characters long. If more_entropy is
 * true, it will be 23 characters.
 * </p>
 * @param more_entropy bool[optional] <p>
 * If set to true, uniqid will add additional
 * entropy (using the combined linear congruential generator) at the end
 * of the return value, which should make the results more unique.
 * </p>
 * @return string the unique identifier, as a string.
 */
function uniqid ($prefix = null, $more_entropy = null) {}