什么是非字母数字字符？

Characters are used to express letters, numbers, signs, etc. Characters are categorized as alphanumeric and non-alphanumeric characters. Alphanumeric characters are consist of alphabet characters and numeric characters. Other than alphanumeric characters are called as non-alphanumeric characters.

字符用于表示字母，数字，符号等。字符分为字母数字字符和非字母数字字符。 字母数字字符由字母字符和数字字符组成。 字母数字字符以外的字符称为非字母数字字符。

Alphanumeric characters consist of alphabet and numeric characters. Alphabet characters can be lower case or upper case.

字母数字字符由字母和数字字符组成。 字母字符可以是小写或大写。

Non-Alphanumeric characters are except alphanumeric characters. space, percent sign, underscore, pipe, colon, semicolon, etc are n