疑問 - VB6.0一個公式轉換的問題

[chung1206]

各位先進們好，今天在做一個公式轉換時遇到了一個問題，我想將公分換成才數，因為30cmX30cm=1才，跟我之前的公式轉換的練習不太一樣，我做了一個Text1公分XText2公分＝Text3才數，然後當我輸入數字後，按下button鈕，可以自動換算才數，請問這個該朝那個方向去寫呢？謝謝。

[mini]

有個方式可以將 Textbox 限制只能輸入 "數字"

OnlyForTextBoxModule.bas

Option Explicit

Private Declare Function SetWindowLong Lib "user32" Alias "SetWindowLongA" _
    (ByVal hWnd As Long, ByVal nIndex As Long, ByVal dwNewLong As Long) As Long
    
Private Declare Function GetWindowLong Lib "user32" Alias "GetWindowLongA" _
    (ByVal hWnd As Long, ByVal nIndex As Long) As Long

Private Const ES_NUMBER = &H2000
Private Const GWL_STYLE = (-16)

'   只允許輸入數字：
Public Function NumbersOnly(tBox As TextBox)
Dim DefaultStyle As Long

    DefaultStyle = GetWindowLong(tBox.hWnd, GWL_STYLE)
    NumbersOnly = SetWindowLong(tBox.hWnd, GWL_STYLE, DefaultStyle Or ES_NUMBER)

End Function

如何使用，只要在 Private Sub Form_Load()裡加上
NumbersOnly TextBox1
就好了