Question

VB运行的问题Private Sub command_click()

Private Sub command_click()
Dim A As Integer, B As Integer, C As Single
Dim D As String
F = InputBox("请输入F的值：")
A = 3B = 5
Select Case F
Case 1: C = A + B: D = "+"
Case 2: C = A - B: D = "-"
Case 3: C = A * B: D = "×"
Case 4: C = A / B: D = "÷"
Case Else: End
End Select
Print C
End Sub

问题：
1.这个程序按理来说输出的结果应该是15，为什么运行没有结果？
2.Case 3: C = A * B: D = "×"中D=“x”具体表示什么意思？

Answer 1

首先，你要在窗体内放入一个按钮控件（CommandButton），默认情况下名称为Command1
然后，程序修改为（共有四处修改）：
Private Sub Command1_Click() '修改1
Dim A As Integer, B As Integer, C As Single
Dim D As String, F As Integer '修改2
F = Val(InputBox("请输入F的值：")) '修改3
A = 3
B = 5
Select Case F
Case 1: C = A + B: D = "+"
Case 2: C = A - B: D = "-"
Case 3: C = A * B: D = "×"
Case 4: C = A / B: D = "÷"
Case Else: End
End Select
Print A; D; B; "="; C '修改4
End Sub

Answer 2

Private Sub command_click()
Dim A As Integer, B As Integer, C As Single
Dim D As String
Me.AutoRedraw = True
F = InputBox("请输入F的值：")
A = 3
B = 5
Select Case F
Case 1: C = A + B: D = "+"
Case 2: C = A - B: D = "-"
Case 3: C = A * B: D = "×"
Case 4: C = A / B: D = "÷"
Case Else: End
End Select
Print C
End Sub

相当于D保存的是运算符，方便以后显示使用。（此段代码没有用到D）

Answer 3

改成这样

Private Sub command1_click()
Dim A As Integer, B As Integer, C As Single
Dim D As String
F = InputBox("请输入F的值：")
A = 3
B = 5
Select Case F
Case 1: C = A + B: D = "+"
Case 2: C = A - B: D = "-"
Case 3: C = A * B: D = "×"
Case 4: C = A / B: D = "÷"
Case Else: End
End Select
Print C
End Sub

Case 3: C = A * B: D = "×"中D=“x”具体表示：
给C赋值，等于A*B
给D赋值，等于“x”，因为定义了D为字符串，赋值D为乘号

追问

懂了
少放了个按钮控件。