这是C++中常用到的处理字符串的相关函数，具有判断某个字符是否是数字或字母等功能，还有字符与整型，浮点型，长整型等的转换，还有字符之间的操作。希望会对大家有所帮助吧-This is the C++ used to handle string correlation function, to determine if the specified character is a numeric or alphanumeric and other functions, there are charact