摘要：
public String getCharset(String file) throws IOException { BufferedInputStream bin = new BufferedInputStream(new FileInputStream(file)); int p = (bin.read() << 8) + bin.read(); String code = null; switch (p) { case 0xefbb: code = "UTF-8"; brea... 阅读全文
摘要：
var regex=/(.).*(\1)/; var str="a sa"; console.log(regex.test(str)); //判断用户输入是否有重复字符 阅读全文