Private Sub Command1_Click()Dim a, b As Integer"--------此處有問題：a是變體，b是integera=Text1.Textb=Text2.TextIf 0<= a <= 100 And 0<= b <=100 Then"----此處重大問題，即問題所在。Text3.Text=aText4.Text=bElseMsgBox "輸入的值不正確"End IfEnd Sub----------------------------------- 說明---------------------------0<= a <= 100 And 0<= b <=100 VB判斷如下：0<=a 如果正確，返回 true （其值 -1），如果錯誤，返回 false(其值 0)。於是-1<= 100 正確，0<= 100 也正確。因此 a為任何值，0<= a <= 100 都為正確，返回 true同理：b為任何值，0<= b <=100 都為正確，返回 true也就是說：a和b為任何值，0<= a <= 100 And 0<= b <=100 都是正確的返回 true 。執行：Text3.Text=aText4.Text=b修改如下：Private Sub Command1_Click()Dim a As Integer, b As Integer‘------------------------------------------1a=Text1.Textb=Text2.TextIf 0<= a and a <= 100 And 0<= b and b <=100 Then"----------------2Text3.Text=aText4.Text=bElseMsgBox "輸入的值不正確"End IfEnd Sub