从System.in读取的整数值不是键入的值 [英] integer value read from System.in is not the value typed

问题描述

我是Java的新手，并且作为一个练习想要一个简单的打印程序需要没有。根据用户的'*'字符。但不知何故，此代码的输出始终保持相似：

I am a newbie to Java, and as an exercise wanted to WAP a simple program to print required no. of '*' characters according to the user. But somehow, the output of this code always remains similar:

package stars;

public class Stars {

    public static void main(String[] args) {

        int no_stars=0;

        try {

            System.out.print("Enter the number of stars:");
            no_stars = (int)System.in.read();

        } catch ( Exception e)    {

            System.out.println("Error! Invalid argument!");
            System.out.println();

        } 

    printstars(no_stars);

    }
    public static void printstars(int n){
        int i;
        for(i=0;i<=n;i++)
        {    
             System.out.println('*');
        }

    }


}

如果我用i替换'*'，我可以看到它循环到50/52/54，即使我运行循环no_stars次。

If I replace '*' with i, I can see that it loops upto 50/52/54, even though i run the loop no_stars times.

这里的问题似乎是什么？

What seems to be the problem here?

推荐答案

因为您正在读取输入字符的ASCII码：

Because you are reading ASCII code of the character from input here:

no_stars = (int)System.in.read();

应该是

no_stars = Integer.parseInt(Console.readLine());

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