1.Scanner类
要想通过控制台进行输入,首先需要构造一个Scanner
对象,并与“标准输入流”System.in
关联
Scanner scanner = new Scanner(System.in);
2.Scanner常用 API
String nextLine( ):
读取输入的下一行内容
Scanner scanner = new Scanner(System.in); String line = scanner.nextLine(); // 输入:how are you? System.out.println(line); // how are you?
String next( ):
读取输入的下一个单词
Scanner scanner = new Scanner(System.in); String line = scanner.next(); // 输入:how System.out.println(line); // how
int nextInt( ):
读取并转化为整数类型
Scanner scanner = new Scanner(System.in); int age = scanner.nextInt(); // 输入:18 System.out.println(age); // 18
double nextDouble( ):
读取并转化为高精度浮点数类型
Scanner scanner = new Scanner(System.in); double score = scanner.nextDouble(); // 输入:521.1314 System.out.println(score); // 521.1314