浙江高中信息技术VB自定义过程和函数

Sub jh(x As Integer,y As Integer)调用时a和x，就是同一个存储
单元，x发生改变，a就好发生
Dim t As Integer
改变。
t=x
变量b和y也同理。
x=y
y=t
End Sub
自定义过程——调用自定义过程
Private Sub Command1_Click()
Dim a As Integer, b As Integer , c As Integer
Sub代表过程
自定义过程——调用自定义过程 Call
Private Sub Command1_Click()
Dim a As Integer, b As Integer
a = 1: b = 9
Call jh(a, b) Text1.Text = Str(a)
jh(a, b)
End Sub
jh(x As Integer, y As Integer)
自定义函数格式
Function 函数名(参数表) As 类型名 <语句块> [函数名=表达式]
End Function
函数体部分实现计算得到一个结果，赋值给函数名！ 函数内部至少有一个te Sub Command2_Click()
Dim x As Integer x = -9
Dim i As Integer, ch As String fact = 0 For i = 1 To Len(x)
_________
If ch >= "0" And ch <= "9" Then fact = fact + 1
_________
Next i End Function
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VB自定义过程和自定义函数
➢自定义过程
VB内部过程（系统提供）
过程
过程名
Private Sub Command1_Click() Dim x As Integer, i As Integer For i = 1 To 5 x=x+i Next i Text1.Text = Str(x)
End Sub
统计文本框输入字符中数字的个数
Private Sub Command1_Click() Dim s As String Dim ans As Integer s = Text1.Text __________ Label1.Caption = "数字有" + Str(ans) + "个"
End Sub Function fact(x As String) As Integer
杜宗飞
End Sub Function myct(x As String, c As String) As Integer
Dim i As Integer, ans As Integer ans = 0 For i = 1 To Len(x)
If Mid(x, i, 1) = c Then ans = ans + 1 Next i myct = ans End Function
Private Sub Command1_Click() Dim s As String Dim n As Integer, m As Integer s = Text1.Text n = myct(s, "a") m = myct(s, "d") Label1.Caption = Str(n + m)
Abs系统函数
y = Abs(x) Text1.Text = Str(y)
Str系统函数
End Sub
函数有返回值，要赋值给某个变量
自定义过程——调用函数
Private Sub Command1_Click()
Dim x As Integer, y As Integer
x = -8
y = myabs(x)
Text1.Text = Str(y)
End Sub
返回
Function myabs(a As Integer) As Integer 值的
If a < 0 Then
类型
myabs = -a Else
myabs(x)
myabs = a End If End Function
myabs(a As Integer) x和a，就是同一个存储单元， a发生改变，x也会改变
a = 1: b = 9 :c = -5 Call jh(a, b) Call jh(a, c) Text1.Text = Str(a) End Sub Sub jh(x As Integer,y As Integer) Dim t As Integer t=x x=y y=t End Sub
➢自定义过程