This expression also removes all null characters and excess whitespace.
此表达式也会删除所有空字符和过量的空白。
For instance, you don't need to check whether the data contains null characters because an XML parser will never pass you a null.
例如，不需要检查数据是否包含空字符，因为XML解析器绝不会传送一个空值。
Normal control characters (characters with values less than 32) : This especially includes character 0, traditionally called NUL; I call it NIL to distinguish it from c's NULL pointer.
常规控制字符(字符值小于32)：还特别包括字符0，传统上称做NUL；我把它称为NIL以区别于c语言中的NULL指针。
The CLP recognizes' null '(specified in uppercase characters) as a null string. For example.
CLP将“NULL”(以大写字符指定)识别为空字符串。
ISO 464 defines null and other graphic characters.
ISO 464定义了空字符(null)和其它图形字符。
I already used this technique above in the split call, which matched the null string (it matches everywhere, so all the characters in the matched string are returned individually).
在split调用中我们就已经使用了这种技术，它可以匹配空字符串(它可以匹配任何地方，因此所匹配的字符串中的所有字符都会一个一个地返回)。
A null string contains zero characters or only Spaces or tabs.
空字符串包含零个字符或只有空格或制表符。
A null string contains zero characters or only Spaces or tabs.
空字符串包含零个字符或只有空格或制表符。
应用推荐