php中的Base64图像preg_replace答案

【问题标题】：Base64 image preg_replace in phpphp中的Base64图像preg_replace
【发布时间】：2015-05-05 20:31:49
【问题描述】：

您好，我在用简单的磅字符“#”替换 base64 嵌入图像时遇到问题，我必须替换的字符串是

SRC = \\“数据：图像/ PNG; BASE64，Y6BkQWnG0Ywf4AiyACMYD4IAfhggAIuAD4wnHwaRNjXOOEHJsjAVnAwDlKhDFNUiCLoRCD2KZW45098i8a + miGXtKPkBdXQO4qZ9096Pmh1v3dytrxhsrR2tlzue1uJShr8JY0BSSMpasCL6 / DiOr9YEZK1BKRKslSJyZToASVSpoTKlL5yJVKmDEgVVImCljY + tkxJy5RUaSMweEjLlJSMowmn51vryY2NVHI9uZFMpX765Wd / MGC19TF1E5t9wGpzmMx2g9Fq7xscHZsCOQ7pD2I4CcEooElGkLKVJhkBCE742fcBR5ikJiMwYVBC0WE6FAEOUqFAkA4EqDAZjuKhMOyPw4FPyeg3weXvsOhXTv + 9MS95vbe / osVUVjX8TsP8kdNz7ypnpCf8JY1hsTIkaqQEDQG + PMCXUyIFVaIMlijJUiVRupUmyl9JE5qjCafnXOvJjbWNdRChfP / jD17I1 + 8YtNn7LVa7xWq32hwWa7 / RZDOZ7YNDY7NzLlDvwHASQXFAExjBUIzYFiVbIcL4aShhghRwh2EKyGsASig6zNAkRISiRDhCUDQRjARCiVBsiY4s + ullmLiHB79y4zHj0EzLh7Z36x1v1y282 + / gDFBCzgp0SQwoJBhAqikRAajyDxiC9OQzEKiviJSDAcppfo0J1g6AsieA8PfoUGv8HD97z + 1XEXqXPMXegYrmtzfNAyeKhx5lCL82ALciANlDRNRC2YrMlXroQONsHlaWfQBHCEKGsmyjiacHq + lUylNlJJ0NOJxKL2 / j4QmxiMZqutz2zp0xssjoERrw / 1B0IYHsigBlN / zeBIRk3k1xvDSdDZYWIQhiYMUBiTFI3QFByikDCNhGk0EkIjISxK41E6EI/Q0UgoFIpQdDxALwap1QC9HKRXwrElOrJCRT6j4/f8sTuzCK5xzJ7rGK1qGz/conmweb60CZad9MtaaWlrUHoSL2+ Bypo8pQqfVAGVNiIHmrCyZvxAc + Ct08HyU6SsmShR + kuUwdLmUNkpji4VCz6 + 1m78Fm6GAzzPV0OD3nYsbqV26vDo0MW2xWEJtYrPa + / oHJqTkEJQPBMNjHJIMm246lZUy1ZkQZjHconWT0g3egSSBI44EgHkhji6Rokko / F + v4bCgUCYUi8VAsSkUiwXAkFI3FEvHEUiSxGI4vLy0urSytLK + s3L6zent1 + fad5ZW7S7fvLq18tnj786XVLxbvcDTh9FxrfSOVTKV + / + OmX6Zm5waERs8WmN5j6 gcmp2bcHh8gBbOHAHvjkqd1gv9gmpBkIL2REghVNg0e0nSY3qQJTYfD4Wgk8gRNIpFYNBqPRuOgIht / kibx + GIslkgklhYXl5eWVpaWVpaXV1dWbt ++ fXdl5Tbbq6t3Vlc5mnB6vrWRTG0kU998 + / + 34xBSYgjWaLP2OQafLg6A4aL4AlICx123bN yyK0cTTpyeUyVTqfWN1Jf3vhoeGXMMDIHlOf2OQa8Pxgk / aL4wy3AATbbt3XA0WV298 / 8BwcTdoNx7r2kAAAAASUVORK5CYII = \\” alt=\\"\\"

代码是

$pattern = '~data\:image\\\/[a-zA-Z]*\;base64\,[a-zA-Z0-9\+\/\\\=]*\=~';
$replacement = '#';
$count = 0;
$rep = preg_replace($pattern, $replacement, $data, -1, $count);

但没有任何反应 - 替换计数为 0；

在 gskinner 的在线正则表达式 http://regexr.com 中，一切正常。

我使用“~”是因为当我使用“/”时 PHP 会发出警告。

对此有什么帮助吗？谢谢！

【问题讨论】：

标签： regex image base64 preg-replace

【解决方案1】：

这样你的反斜杠太多了。例如。 \\\/ 表示 a backslash + an escaped forward slash。

这适用于 ~ 分隔符：

$re = "~data:image/[a-zA-Z]*;base64,[a-zA-Z0-9+/\\=]*=~"; 
$str = "src=\\\"data:image/png;base64,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\\\" alt=\\\"\\\""; 
$subst = "#"; 
echo preg_replace($re, $subst, $str);

sample program 的结果：

src=\"#\" alt=\"\"

【讨论】：

真的好用！起初我认为每个 base64 编码都以“=”符号结尾 - 似乎不是，必须从正则表达式中删除一个，现在看起来像这样 ~data:image/[a-zA-Z]*;base64,[a-zA-Z0-9+/=]*~。感谢您的快速回复。
不客气。是的，Base64 的不同实现可以以不同的字符结尾。如果答案对您有用，也请考虑投票。