如何使用c＃交换四位数的数字？ [英] How to swap numbers of four digits numbers using c#?

问题描述

我想交换输入用户的四位数字。我写了那些代码

  private   void  btnSwap_Click（ object  sender，EventArgs e）
 {
  int  number，digit1，digit2，digit3，digit4; 
 number = Convert.ToInt32（txtNumber.Text）; 
 digit1 = number％ 10 ; 
 digit2 =（数字/  10 ）％ 10 ; 
 digit3 =（数字/  100 ）％ 10 ; 
 digit4 =（数字/  1000 ）％ 10 ; 
 digit4 = digit1; 
 digit1 = digit3; 
 digit3 = digit2; 
 digit2 = digit1; 
 lbReserved.Text = number.ToString（）; 
 
} 
 

但是这些代码返回相同的数字？怎么做？

解决方案

参考：反转字符串的最佳方法 [ ^ ]

 lbReserved.Text =  new  < span class =code-sdkkeyword> String （Array.Reverse（txtNumber.Text.ToCharArray（）））; 
 

当然，最好的答案是DamithSL（五位顺便说一下）。但我认为你应该理解你在代码中做了什么。



第一部分是OK：

  int  number，digit1，digit2，digit3，digit4; 
 number = Convert.ToInt32（txtNumber.Text）; 
 digit1 = number％ 10 ; 
 digit2 =（数字/  10 ）％ 10 ; 
 digit3 =（数字/  100 ）％ 10 ; 
 digit4 =（数字/  1000 ）％ 10 ; 

如果你刚刚调试了这个，你会发现在此之后你已经有了相反的数字（如果数字是1234，那你就得到了这个数字） 4位数字1,3位数字2 ...）

所以简单地添加：

 lblReserved.Text =  string  .Concat（digit1，digit2，digit3，digit4）; 

会给你正确答案。



而不是那样，你开始按照特定顺序分配值，你必须明白，在给变量赋值后，前一个值就会丢失。这是胡说八道。



最后，你给lbReserved原始值（lbReserved.Text = number.ToString（）），所以当然你看到的是原版价值。



很抱歉这个答案很长，但是看到代码看起来你是一个新手并且有一些错误的概念值得一解。 ：）

因为你在赋值中使用了已经改变的值。

交换两个数字的正确逻辑，比如说 d1 和 d2 是：

  int  tmp; 
 tmp = d1; 
 d1 = d2; 
 d2 = tmp;  //  这会将d1的旧（正确）值分配给d2  
 

I want to swap numbers of four digits number that enter users. And I wrote that codes

private void btnSwap_Click(object sender, EventArgs e)
       {
           int number, digit1, digit2, digit3, digit4;
           number = Convert.ToInt32(txtNumber.Text);
           digit1 = number % 10;
           digit2 = (number / 10) % 10;
           digit3 = (number / 100) % 10;
           digit4 = (number / 1000) % 10;
           digit4 = digit1;
           digit1 = digit3;
           digit3 = digit2;
           digit2 = digit1;
           lbReserved.Text = number.ToString();

       }

But that codes return same number ? How to do it?

解决方案

refer : Best way to reverse a string[^]

lbReserved.Text = new String(Array.Reverse(txtNumber.Text.ToCharArray()));

Of course,the best answer is DamithSL's (fived btw). But I think you should understand what you are doing in your code.

The first part is OK:

int number, digit1, digit2, digit3, digit4;
number = Convert.ToInt32(txtNumber.Text);
digit1 = number % 10;
digit2 = (number / 10) % 10;
digit3 = (number / 100) % 10;
digit4 = (number / 1000) % 10;

If you just had debugged this, you'd see that after this,you already have the numbers in reverse order (if number is 1234, you've got after this 4 in digit1,3 in digit 2...)
So simply adding:

lblReserved.Text=string.Concat(digit1,digit2,digit3,digit4);

would have given you the right answer.

Instead of that, you start assigning the values in no specific order, and you must understand that after you give a variable a value,the previous one is lost. It's a nonsense.

Finally, you give the lbReserved the original value (lbReserved.Text=number.ToString()), so of course what you see is the original value.

Sorry for the long answer,but seeing the code it seems you are a newbie and have some wrong concepts that deserved an explanation. :)

Because you are using, in assignments, already changed values.
The correct logic to swap two numbers, say d1 and d2 is:

int tmp;
tmp = d1;
d1 = d2;
d2 = tmp; // this assigns the old (correct) value of d1 to d2

这篇关于如何使用c＃交换四位数的数字？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！