These functions all manipulate strings in various ways. Some more specialized sections can be found in the regular expression and URL handling sections.
For information on how strings behave, especially with regard to usage of single quotes, double quotes, and escape sequences, see the Strings entry in the Types section of the manual.
建立這個延伸不需要任何外部程式庫。
這些函數是PHP核心的一部分,不需要安裝就可使用。
以下的常數由此延伸定義,只在這個延伸被編譯成PHP或實行時期被動態載入時有效。
For even more powerful string handling and manipulating functions take a look at the POSIX regular expression functions and the Perl compatible regular expression functions.