[菜菜问题]关于在textbox判断问题
[菜菜问题]关于在textbox判断问题
简单例子，在一个txtbox输入1-7数字时，另一个txtbox显示monday-sunday
我要增加一个判断，即不是1-7数字时，显示“error“
但我输入非数字时，为什么程序出错？我已经强制转换了~cint~请高手给解释下。谢谢

VB.NET code

Private Sub btnShowDay_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnShowDay.Click        Dim DaysofTheWeek(6) As String        DaysofTheWeek(0) = "Monday"        DaysofTheWeek(1) = "Tuesday"        DaysofTheWeek(2) = "Wednesday"        DaysofTheWeek(3) = "Thursday"        DaysofTheWeek(4) = "Friday"        DaysofTheWeek(5) = "Saturday"        DaysofTheWeek(6) = "Sunday"        'Dim number As Integer        'number = CInt(txtIndex.Text)        If CInt(txtIndex.Text) >= 0 And CInt(txtIndex.Text) < 7 Then            txtDay.Text = DaysofTheWeek(CInt(txtIndex.Text) - 1)            Label2.Visible = True            txtDay.Visible = True        Else : txtDay.Text = "ERROR"        End If    End Sub

[解决办法]
因为你的txtIndex.Text里输入的值不是数值，那么cint强制转换肯定会报错，你这里应该加上Try，用于捕获错误并处理。