Question

VB设计一个秒表模拟程序

1．设计一个秒表模拟程序，按下“开始”按钮，屏幕显示当前时间；按下“结束”按钮，屏幕显示结束时间和持续时间；按下“退出”，结束程序

Dim a As Date
Dim b As Date
Private Sub Command1_Click()
a = Time
Text1.Text = a
End Sub

Private Sub Command2_Click()
b = Time
Text2.Text = b
Text3.Text = Format(DateDiff("s", a, b), "00:00:00")
End Sub
Private Sub Command3_Click()
End
End Sub
已经实现了秒表的功能 不过 只能计时到00：00：99才能变成00:01:00跪求高手指导让他变成当秒表到00:00:59然后进位成00:01:00 谢谢 感激不尽

Answer 1

Text3.Text = Format(DateDiff("s", a, b), "00:00:00")
改成如下：
Text3.Text = Format(b - a, "hh:mm:ss")

Answer 2

Dim a As Date
Dim b As Date
Private Sub Command1_Click()
a = Time
Text1.Text = a
End Sub

Private Sub Command2_Click()
b = Time
Text2.Text = b
Text3.Text = Format(DateDiff("s", a, b), "00:00:00")
End Sub
Private Sub Command3_Click()
End
End Sub

Answer 3

Private Sub Command2_Click()
b = Time
Text2.Text = b
tt = DateDiff("s", a, b)
TmpH = tt \ 3600
TmpM = (tt Mod 3600) \ 60
TmpS = tt Mod 60
Text3.Text = Format(TmpH & ":" & TmpM & ":" & TmpS, "HH:MM:SS")
End Sub