输入流读取器 - 读取方法返回错误的值 [英] Input stream reader- read method return wrong value

问题描述

这可能听起来很容易或者是一个古老的愚蠢问题，但对我来说却完全不同。
我为半降金字塔模式编写了一个程序，就像这样。

This may sound very easy or an old stupid question, but it is quite different for me. I have written a Program for a half-Descending pyramid Pattern which is like this.

1

1 2

1 2 3

1 2 3 4

1 2 3 4 5

1 2 3 4 5

我知道这很容易，诀窍是我不想通过使用<$ c $来做到这一点c>扫描仪和 Integer.parseInt（）。我试图用 BufferedReader 和 InputStreamReader 来做到这一点。
所以当我执行以下代码的main方法时输入为5的num。当我打印它时，它读为53。我不知道为什么会这样。但是当我使用'Integer.parseInt（br.readLine（））'方法时，它会给出准确的输出。当read方法应该读取int值时，它应该如何发生。请清除它。

I know this is very easy, the trick is I don't wanna do this by use of Scanner and Integer.parseInt(). I am trying to do this with BufferedReader and InputStreamReader. So when I execute the following code of my main method with a input of 5 in num. It reads it as 53 when I print it. I have no idea why it's happening. But when I use the 'Integer.parseInt(br.readLine())' method it gives the exact output. How is it supposed to happen when read method is supposed to read int values. Please clear it.

    int num1;   
    BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
    System.out.println("Enter hte value of num1");
    //num1=Integer.parseInt(br.readLine());
    num1=br.read();
    System.out.println(num1);
    for(int i=0;i<num1;i++)
    {
        for(int j=0;j<=i;j++)
        {
            System.out.print(j+"\t");

        }
        System.out.println();
    }

这是我的第一个问题所以请忽略愚蠢的错误，我试着写尽我所能。
谢谢..

It's my first question so please ignore the silly mistakes, I have tried to write it as best as I could. Thanks..

推荐答案

当我打印它时，它读为53。 / p>

It reads it as 53 when i prints it.

是的，它会。因为你正在调用 read（），它返回一个字符，或-1表示数据结束。

Yes, it would. Because you're calling read() which returns a single character, or -1 to indicate the end of data.

字符'5'的Unicode值为53，这就是你所看到的。 （毕竟，你的变量是 int 。）如果你将 num1 强制转换为 char ，你会看到'5'。

The character '5' has Unicode value 53, so that's what you're seeing. (Your variable is an int, after all.) If you cast num1 to a char, you'll see '5' instead.

当你想要转换整数的文本表示时进入整数值，通常会使用 Integer.parseInt 等代码。

When you want to convert the textual representation of an integer into an integer value, you would usually use code such as Integer.parseInt.

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