VB常用的数据类型有:
整型(Integer,表示-32768至32767之间的整数)
长整型(Long,表示-2,147,483,648至2,147,483,647之间的整数)
实型(Single,表示-3.37E+38至3.37E+38之间的实数)
双精度实型(Double,表示-1.67E+308至1.67E+308之间的实数)
字符(String,每个字符占一字节,可以储存0~65,535个字符)
布尔(Boolean,只有两个值True/-1,或False/0)。
有时为了简便,也以符号进行简单的定义,作用是和上面一样的。
整型可以用“%”代替,
长整型可以用“&”代替,
实型可以用“!”,
双精度实型可以用“#”
DO UNTIL….LOOP
Private Sub Form_DblClick()
Dim i%, n%, mySum&
n = Val(InputBox("请输入要一个整数:"))
mySum = 1
Do Until i = n
i = i + 1
mySum = mySum * i
If n > 12 Then Exit Do
Loop
Print mySum
End Sub
多重循环
Private Sub Form_Click()
Dim i%, j%
For i = 1 To 3
For j = 1 To 3
Print "i="; i; "j="; j
Next j
Next i
End Sub
换零钱
Private Sub Form_Click()
Dim x%, y%, z%, n%
Print "5元个数", "10元个数", "20元个数"
For x = 0 To 20
For y = 0 To 10
For z = 0 To 5
If 5 * x + y * 10 + z * 20 = 100 Then
n = n + 1
Print x, y, z
End If
Next z
Next y
Next x
Print "共有" & n & "种换法"
End Sub
设置窗体与按钮部分属性
Private Sub Form_Load()
With Form1
.Height = 10000: .Width = 10000
With Command1
.Height = 2000: .Width = 2000
.Caption = "按钮高度与宽度都是2000"
Form1.Caption = "窗体高度与宽度都是10000"
End With
End With
End Sub
练习1:
判断如果a>60,I=1;a>70,I=2;a>80,I=3;a>90,I=4
Private Sub Form_Click()
Dim a%, i%
a = Val(InputBox("请输入一个数", , 0))
If a > 90 Then
i = 4
ElseIf a > 80 Then
i = 3
ElseIf a > 70 Then
i = 2
ElseIf a > 60 Then
i = 1
Else
End
End If
Print "I="; i
End Sub
练习2:
计算增加工资:1000以上,增加20%;800以上,增加15%;其余增加10%。
Private Sub Form_Click()
Dim a%, total%
a = Val(InputBox("请输入一个基准工资", , 0))
If a >= 1000 Then
total = a * 1.2
ElseIf a >= 800 Then
total = a * 1.15
ElseIf a >= 0 Then
total = a * 1.1
Else
Text1.Text = "请输入正整数"
End If
Text1.Text = total
End Sub
练习3
将a、b两个值中较小的值输出到text中。
Private Sub Form_Load()
Dim a%, b%
a = Val(InputBox("请输入a值:", , 0))
b = Val(InputBox("请输入b值:", , 0))
If a > b Then
Text1.Text = b
Else
Text1.Text = a
End If
End Sub
冒泡排序
Dim a(9) As Long
Private Sub Command1_Click()
Dim i As Long, j As Long, b As Long
For i = 1 To 9
For j = 0 To 9 - i
If a(j) < a(j + 1) Then
b = a(j)
a(j) = a(j + 1)
a(j + 1) = b
End If
Next j
Next i
For i = 0 To 9
Text1.Text = Text1.Text + CStr(a(i)) + " "
If i = 4 Then Text1.Text = Text1.Text + Chr(13) + Chr(10)
Next i
End Sub
Private Sub Command2_Click()
Dim i As Long, l
Text1.Text = ""
For i = 0 To 9
N:
l = InputBox("请输入排序的10个数字,这是第" & CStr(i + 1) & "个", "提示", "")
If IsNumeric(l) Then
a(i) = l
Else
MsgBox "请输入数字", vbOKOnly, "错误"
GoTo N
End If
Next i
End Sub
动态数组
Private Sub Command1_Click()
Text1.Text = ""
Dim s As Long, i As Long
Dim a()
Do
ReDim Preserve a(s)
a(s) = InputBox("请输入字符串,输入空串时结束", "输入")
s = s + 1
Loop Until a(s - 1) = ""
For i = 0 To s - 2
Text1.Text = Text1.Text & "第" & CStr(i + 1) & "个是”" & CStr(a(i)) & ""
Next i
Erase a
End Sub