Case語句只運行一個條件

Question

嘿，當我在我的case語句中輸入一個整數時，它會產生正確的輸出，但是使用一個字符串，每次只產生相同的結果，你們是否知道任何解決方案？

 Select Case Grades.Text 
     Case = "A*" 
      score = score + 100 
      MessageBox.Show("You entered an A*") 
      Gcount = Gcount + 1 

     Case >= 90 
      score = score + 100 
      MessageBox.Show("You entered an A*") 
      Gcount = Gcount + 1 

     Case = "A" 
      score = score + 85 
      MessageBox.Show("You entered an A") 
      Gcount = Gcount + 1 
      MessageBox.Show(Gcount) 

     Case < 90 And Grades.Text >= 80 
      score = score + 85 
      MessageBox.Show("You entered an A") 
      Gcount = Gcount + 1 
      MessageBox.Show(Gcount) 

     Case = "B" 
      score = score + 75 
      MessageBox.Show("You entered a B") 
      Gcount = Gcount + 1 
      MessageBox.Show(score) 

     Case < 80 And Grades.Text >= 70 
      score = score + 75 
      MessageBox.Show("You entered a B") 
      Gcount = Gcount + 1 

     Case = "C" 
      score = score + 65 
      MessageBox.Show("You entered a C") 
      Gcount = Gcount + 1 

     Case < 70 And Grades.Text >= 60 
      score = score + 65 
      MessageBox.Show("You entered a C") 
      Gcount = Gcount + 1 

Answer 1

試試這個：

Select Case Grades.Text 
     Case Is >= 90 
      MessageBox.Show("You entered an A*") 
     Case Is < 90 And Grades.Text >= 80 
      MessageBox.Show("You entered an A") 
     Case Is < 80 And Grades.Text >= 70 
      MessageBox.Show("You entered a B") 
     Case Is < 70 And Grades.Text >= 60 
      MessageBox.Show("You entered a C") 
    End Select 

Answer 2

您應該設置選項嚴格上。

所以有這樣的

Select case True 
    Case intVariable <= 90 
    ' do something... 
    Case 91 < intVariable AndAlso intVariable <= 100 
    ' do something... 
    Case 100 < intVariable AndAlso intVariable <= 110 
    ' do something... and so on 
End Select