VB求最大值函数

双击command1，写下
dim a as string
dim amax as integer,temp as integer
a=trim(text1)'去除text1中的空格，将值赋给a
amax=0'设置amax的初值，因为是找最大值，所以取0
for i=1 to len(a)'循环，从1到a的长度
temp=val(mid(a,i,1))'从a中第i个位子取一个数
if temp>=amax then amax=temp'和最大值比较
next i
text2=amax

function
maxfound(a()
as
long)
'long可修改为其它类型，以适应不同的要求

dim
nummax

nummax
=
a(1)

for
i
=
2
to
8

if
nummax
<
a(i)
then

nummax
=
a(i)

end
if

next
i

maxfound
=
nummax
end
function

函数条用格式：变量=maxfound(long型数组)，则最大值别存储到变量中

两个文本框，一个按钮
Option Base 1
Private Sub Command1_Click()
Dim max As Integer
If Text1.Text = "" Then
MsgBox "文本不能为空"
Exit Sub
End If
max = Mid(Text1, 1, 1)
For i = 2 To Len(Text1.Text)
If Mid(Text1.Text, i, 1) > max Then
max = Mid(Text1.Text, i, 1)
End If
Next i
Text2.Text = max
End Sub

Option Explicit

Private Sub Command1_Click()
Dim l As Integer, max As Integer
Dim i As Integer, a As Integer
l = Len(Text1.Text)
If IsNumeric(Text1.Text) = False Then MsgBox "text1内不是数字"
max = Left(Text1.Text, 1)
For i = 2 To l
a = Mid(Text1.Text, i, 1)
If a > max Then max = a
Next
Text2.Text = max
End Sub

Private Sub Form_Load()
Text1.Text = ""
Text2.Text = ""
End Sub

Private Sub Command1_Click()
Dim i As Integer
For i = 9 To 0 Step -1
If InStr(1, Text1.Text, i) > 0 Then Text2.Text = i: Exit Sub
Next
End Sub