visual basic(否则必须先匹配if或elseif)

时间:2015-07-30 04:44:35

标签: vb.net

 Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
    If Not IsNumeric(TextBox1.Text) Or TextBox1.Text = "" Or ComboBox1.Text = "" Then MsgBox("Please enter numbers only and dont  leave blanks")
    else
    Dim newdog, newcat As Integer

    newcat = 25 + 4 * TextBox1.Text
    newdog = 21 + 4 * TextBox1.Text

其他用蓝色加下划线并且一直说“其他必须先匹配if或elseif” 顺便说一句,我试图制作一个年龄转换器

1 个答案:

答案 0 :(得分:0)

你的第一行是一行if语句,因为你已将执行的代码直接放在“Then”之后,所以当你到达下一行时,你已经离开了if语句。

通过将Msgbox移动到下一行(并包括End If,如前所述),您的问题将得到解决:

If Not IsNumeric(TextBox1.Text) Or TextBox1.Text = "" Or ComboBox1.Text = "" Then 
    MsgBox("Please enter numbers only and dont  leave blanks")
else
    Dim newdog, newcat As Integer

    newcat = 25 + 4 * TextBox1.Text
    newdog = 21 + 4 * TextBox1.Text
end if

或在Then和msgbox命令之间放一个冒号 - 这是新行的简写:

If Not IsNumeric(TextBox1.Text) Or TextBox1.Text = "" Or ComboBox1.Text = "" Then : MsgBox("Please enter numbers only and dont  leave blanks")
else
    Dim newdog, newcat As Integer

    newcat = 25 + 4 * TextBox1.Text
    newdog = 21 + 4 * TextBox1.Text
end if