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php一些功能强大的字符串处理函数总结

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Jun 20, 2016 pm 01:00 PM

php string

php一些功能强大的字符串处理函数总结

列举几个php语言中被遗忘的一些但功能非常强大的字符串处理函数，这里就不对其用法一个个举例了，感兴趣的朋友可以自己测试。

(PHP 4 >= 4.0.4, PHP 5)

1、ctype_alnum
检测是否是只包含[A-Za-z0-9]

2、ctype_alpha

检测是否是只包含[A-Za-z]

3、ctype_cntrl
检查是否是只包含类是"\r\b\t"之类的字符控制字符

4、ctype_digit
检查时候是只包含数字字符的字符串（0-9）

5、ctype_graph
检查是否是只包含有可以打印出来的字符（除了空格）的字符串

6、ctype_lower
检查是否所有的字符都是英文字母，并且都是小写的

7、ctype_print
检查是否是只包含有可以打印出来的字符的字符串

8、ctype_punct
检查是否是只包含非数字/字符/空格的可打印出来的字符

9、ctype_space
检查是否是只包含类是"\r\b\t"之类的字符和空格

10、ctype_upper
检查是否所有的字符都是英文字母，并且都是大写的

11、ctype_xdigit
检查是否是16进制的字符串，只能包括"0123456789abcdef"

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