Private Sub Command1_Click()
Dim bfi#, b#, hi#, hfi#, γ0#, Md#, h0#, fcd#, fsd#, ξb#, ρmin#, Mu1#, x#, A#, ρ#
bfi = Val(txt1.txt)
b = Val(txt2.txt)
hi = Val(txt3.txt)
hfi = Val(txt4.txt)
γ0 = Val(txt5.txt)
Md = Val(txt6.txt)
h0 = Val(txt7.txt)
fcd = Val(txt8.txt)
fsd = Val(txt9.txt)
ξb = Val(txt10.txt)
ρmin = Val(txt11.txt)
Mu1 = fcd * bfi * (h0 - 0.5 * hfi)
If (γ0 * Md > Mu1) Then
  x = h0 - (h0 * h0 - 2 * γ0 * Md / (fcd * b) + 2 * (bfi - b) * hfi * (h0 - 0.5 * hfi) / b) ^ 0.5
  If (x > ξb * h0) Then
    MsgBox "少筋"
  Else
    A = (fcd * b * x + fcd * hfi * (bfi - b)) / fsd
    ρ = A / (b * h0)
    If (ρ - ρmin > 0 Or ρ - ρmin = 0) Then
         Print "As="; A
         Else
         MsgBox "少筋"
    End If
 End If
Else
 x = h0 - (h0 * h0 - 2 * γ0 * Md / (fcd * bfi)) ^ 0.5
 A = fcd * bfi * x / fsd
 ρ = A / (b * h0)
   If (ρ - ρmin > 0 Or ρ - ρmin = 0) Then
     Print "As="; A
   Else
    ρ = ρmin
运行后出现实时错误424要求对象，请问各位大神如何解决，本人菜鸟，乃工科生一枚，只因做课程设计要编程，还望大家不吝赐教！