标准控制台输入

Question

下午好

我只想知道使用java进行标准控制台输入的最简单方法。当它涉及到整型或双精度输入时，例如在C#中，它很简单。在java中做这件事最简单的方法是什么？

double a;
        Console.WriteLine("Please enter the value");

        a = double.Parse(Console.ReadLine());

        Console.WriteLine("thank you for entering " + a);

仁慈地问候阿里安

Answer 1

直接转换为：

Scanner scan = new Scanner(System.in);
System.out.println("Please enter the value");
double i = Double.parse(scan.nextLine());
System.out.println("thank you for entering " + i);

但您也可以使用Scanner#nextDouble()

Scanner scan = new Scanner(System.in);
System.out.println("Please enter the value");
double i = scan.nextDouble();
System.out.println("thank you for entering " + i);

Answer 2

try {
      InputStreamReader isr = new InputStreamReader(System.in);
      BufferedReader br = new BufferedReader(isr);
      String s = br.readLine();
      DecimalFormat df = new DecimalFormat();
      Number n = df.parse(s);
    double d = n.doubleValue();
     } catch (IOException e) {
        e.printStackTree();
     } catch (ParseException e) {
       e.printStackTree();
     }

或

   try {
          InputStreamReader isr = new InputStreamReader(System.in);
          BufferedReader br = new BufferedReader(isr);
          String s = br.readLine();
          double d = Double.parseDouble(s);

        } catch (IOException e) {
         e.printStackTree();
        } catch (ParseException e) {
         e.printStackTree();
        }

Answer 3

使用java.util.Scanner -它支持从标准输入中读取数字。