简单的求VB最大最小值

private sub form_click()
dim a(4) as single,i as integer,j as integer
for i=1 to 3
for j=i+1 to 4
If a(i) > a(j) Then
a(0) = a(j)
a(j) = a(i)
a(i) = a(0)
next
next
print "从大到小的顺序是："
print a(1),a(2),a(3)，a(4)
end sub

因为我也是新手，所以我用最苯的方法
首先在窗体上准备6个文本框，一个命令按纽，3个标签。其中4个文本text1到text4用来输入数据，另外2个文本text5和text6用来显示最大和最小值，2个标签分别对应这2个文本
代码如下
Private Sub Command1_Click()
Dim a(3) As Double, max As Double, min As Double
a(0) = Text1.Text: a(1) = Text2.Text: a(2) = Text3.Text: a(3) = Text4.Text
If a(0) < a(1) Then max = a(1): min = a(0) Else max = a(0): min = a(1)
If max < a(2) Then max = a(2)
If max < a(3) Then max = a(3)
If min > a(2) Then min = a(2)
If min > a(3) Then min = a(3)
Text5.Text = max: Text6.Text = min
End Sub

Private Sub Form_Load()
Text1.Text = ""
Text2.Text = ""
Text3.Te