Java中Scanner的常用方法总结(一次学懂)

import java.util.Scanner;
 
public class Main {
	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);
		int a = scanner.nextInt();
		double b = scanner.nextDouble();
		System.out.println(a);
		System.out.println(b);
	}
}

import java.util.Scanner;
 
public class Main {
	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);
		int n = scanner.nextInt();//定义数组长度为n
		int[] arr = new int[n];//定义一个长度为n，名叫arr的数组
		for (int i = 0; i < n; i++) {
			arr[i]=scanner.nextInt();
		}
		System.out.print("Scanner输入的数组为:");
		for (int i = 0 ; i < n ; i++) {
			System.out.print(arr[i]+" ");			
		}
	}
}

import java.util.Scanner;
 
public class Test2 {
	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);
		int n = scanner.nextInt();
		int m = scanner.nextInt();
		int[][] mat = new int[n][m];
		System.out.println("请输入整数型的二维数组:");
		for (int i = 0; i < n; i++) {
			for (int j = 0; j < m; j++) {
				mat[i][j]=scanner.nextInt();
			}
		}
		for (int i = 0; i < n; i++) {
			System.out.print("[");
			for (int j = 0; j < m; j++) {
				if(j==m-1) {
					System.out.print(mat[i][j]);
				}else {
					System.out.print(mat[i][j]+",");
				}
			}
			System.out.print("]");
			System.out.println();
		}
	}
}

import java.util.Scanner;
 
public class Main {
	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);
		int n = scanner.nextInt();
		String[] arr = new String[n];
		for(int i = 0 ; i < n ; i ++) {
			arr[i]=scanner.next();
		}
		System.out.println("输入的字符串数组为:");
		for (int i = 0; i < arr.length; i++) {
			System.out.print(arr[i]);
		}
		
	}
}

import java.util.Random;
import java.util.Scanner;
 
public class ScannerDemo {
	public static void main(String[] args) {
		Random r = new Random();
		int num = r.nextInt(100);
		int input = -1;
		Scanner scanner = new Scanner(System.in);
		while(true) {
			System.out.println("猜一猜随机数是多少？");
			input=scanner.nextInt();
			if (input>num) {
				System.out.println("你输入的数字大了！");
			}else if(input<num) {
				System.out.println("你输入的数字小了！");
			}else if(input==num) {
				break;
			}else {
				System.out.println("您的输入有误！");
			}
		}
		System.out.println("恭喜你答对了！");
		scanner.close();
	}
}

 String s = "you are  Beautiful!you are kind! you are smart!";
        Scanner scanner = new Scanner(s);
        scanner.useDelimiter("!");
 
        while (scanner.hasNext())
            System.out.println(scanner.next());