1. 我知道 For ...next 結構
For 迴圈變數 = 初值 To 終值 [Step 增量]
陳述區塊
Next [迴圈變數]
2. 我會計算 for...next 迴圈的執行次數
(終值-初值)/增量+1
3. 印出 5 10 15 ... 50
Public Class Form1
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
'印出 5 10 15 ... 50
Dim ans As String
For i = 5 To 50 Step 5
ans &= RSet(i, 4)
Next
Me.TextBox1.Text = ans
End Sub
End Class
4. 印出 20 16 12 ...-12 -16
Public Class Form1
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
'印出 20 16 12 ...-12 -16
Dim ans As String
For i = 20 To -16 Step -4
ans &= RSet(i, 4)
Next
Me.TextBox1.Text = ans
End Sub
End Class
5. 我知道 do while....loop 結構
Do While 條件
程式區塊
Loop
6. 我知道 do until....loop 結構
Do Until 條件
程式區塊
Loop
7. 我知道 do ...loop while 結構
Do
程式區塊
Loop While 條件
8. 我知道 do...loop until 結構
Do
程式區塊
Loop Until條件
9. 如何將 For...Next 改成 Do While...Loop 或 Do...Loop While?
For I=初值 to 終值 step 增量
⁞
Next
實例
For x = 20 to -16 step -4 Dim ans as string
Dim i as string = 20
Ans &=x & “ “ Do While i >= -16
ans &= i & " "
Next
Next Msgbox (ans)
Msgbox (ans)
10. 印出九九乘法表。(三種不同樣式)
Public Class Form1
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
'印出九九乘法表。(1)
Dim ans As String
For i = 1 To 9
For j = 1 To 9
ans &= RSet(i * j, 4)
Next
ans &= vbNewLine
Next
Me.TextBox1.Text = ans
End Sub
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
'印出九九乘法表。(2)
Dim ans As String
For i = 1 To 9
For j = 1 To 9
ans &= i & "*" & j & "=" & LSet(i * j, 2) & vbTab
Next
ans &= vbNewLine
Next
Me.TextBox2.Text = ans
End Sub
Private Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click
'印出九九乘法表。(3)
Dim ans As String
For i = 1 To 9
For j = 1 To i
ans &= i * j & " "
Next
ans &= vbNewLine
Next
Me.TextBox3.Text = ans
End Sub
End Class
