Visual Basic循环永不结束

Question

我试图在Visual Basic中打印一个菱形。我的代码的上半部分工作完美，但由于某种原因，我无法让下半部分以类似的方式工作。在下半部分，在o（用于制作钻石）之后打印出空格，而o的数量减少会将程序发送到无限循环？谁能帮忙？

下半部分可能是完全错误的，我还在上

在这里工作是代码：

Option Explicit On 
Imports System 

Module diamond 
    Sub Main() 
     ' The o variable will make the "o" part of the diamond, the space variable will be for places without an "o". 
     Dim row, spaces, o as Integer 
     'Dim index as integer 

     'For top half 
     ' Count the row number. 
     row = 1 
     spaces = 9 
     o = 1 
     Do until row = 20 
      ' Count of row increases every loop until half of diamond is done. 
      row +=1 
      ' Write 1 less space every line. 
      For row = 1 to spaces 
       console.write(" ") 
      Next row 
      spaces -=1 
      'Write 2 more "o"'s every loop. 
      For row = 1 to o 
       Console.write("o") 
      Next row  
      o +=2 
      Console.Writeline 
     Loop 
     'Top of the diamond is done 

     'This is the bottom half, which will not work. 
     row = 20 

     Do until row = 40 
      row +=1 
      For row = 20 to spaces 
       Console.write(" ") 
      Next row 
      spaces +=1 
      'Write 2 less "o"'s every loop. 
      For row = 20 to o 
       Console.write("o") 
      Next row  
      o -=2 
      Console.Writeline 
     Loop 
    End Sub 
End Module 

Answer 1

的问题是，你使用row为您的出行计数器为while循环，也作为for循环的循环索引。上半场工作完全是偶然的。 row下半年永远不会达到40，因为它不断被for循环劫持。

尝试For i = 20 to spaces等等。