示例： 判断字符串是否由字母数字下划线组成： using System; using System.Diagnostics; using System.Text.RegularExpressions; namespace ConsoleApp6 { class Program {[......]继续阅读

Example: Determining whether a string consists of alphanumeric characters and underscores: using System; using System.Diagnostics; using System.Text.R[......]继续阅读