Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim rndnum As String
Dim pic1 As New PictureBox
Dim num1, a As String
Dim j, s As Integer
Dim verifycode As String
Randomize()
rndnum = ""
Do While Len(rndnum) < 4
num1 = CStr(Chr((57 - 48) * Rnd() + 48))
rndnum = rndnum & num1
Loop
verifycode = rndnum
For j = 1 To Len(verifycode)
a = Mid(verifycode, j, 1)
s = Int(a)
pic1 = Controls("picturebox" & j)
pic1.Image = ImageList1.Images.Item(s)
Next
session1 = verifycode
End Sub

牛逼

卧槽，这界面够花里胡俏的。背景图用的像PPT😂

确实是一种可行的思路