如何使用PHP编码字符串里面的序列号吗？

How to encode strings inside serial number using PHP?

youdao

你决定亲自试一试：选择一个替换表并用它来编码字符串。

You decided to try it out: you chose some specific substitution table and used it to encrypt some strings.

youdao

行4编码字符串Double secret probation并使用Base64将加密了的这个字符串转变为可打印的字符，以便于用电子邮件等程序传输。

Line 4 encodes the string Double secret probation and USES Base64 to turn the encrypted string into printable characters that can easily be transmitted over E-mail, say.

youdao

Last time we used printf generally to print a static string, like a hardcoded string, like "David," just for example's sake.

上次我们通常用“printf“,来打印一个静态的字符串，像硬编码的字符串“David“,这只是个例子。

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