the purpose of this program is to parse expressions from an input file and display token type and value in an output file

C#词法分析器 Lexical Scanner 能够实现输入的字符串按照词法切成小片段token 比方说 输入1+2+for 就会得到 1 digit + operator 2 digit + operator for reserved Word-This scanner was developed in Microsoft visual C# 2010 Express platform, which can only lexical analysis about the input phras