VB.Net语法规则的3个实例

乐博网lob.cn提示：调试环境为 vs2005 +  windows2003 / windows2008 / xp / vista

实例1：

同 Integer 类型的变量比较 

Public Class CompareForm

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim A As Integer = 10
        Dim B As Integer = 20
        If A <= B Then
            MessageBox.Show("乐博网提示：A<=B")
        Else
            MessageBox.Show("乐博网提示：A>B")
        End If
    End Sub
End Class

实例2：

Boolean变量的比较

Public Class LogicForm

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim a As Boolean = True
        Dim b As Boolean = False
        If a And b = True Then  ''和If a And b Then相同
            MessageBox.Show("乐博网提示：a和b都是True ")
        Else
            MessageBox.Show("乐博网提示：a和b有一个不是True ")
        End If

    End Sub
End Class

实例3：

同String类型变量比较  String和Integer不同变量的比较

Public Class StrForm

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim str1, str2 As String
        str1 = "Hello"
        str2 = "World"
        MessageBox.Show("乐博网提示：" & str1 + " " + str2)  ''MessageBox.show(str1 & " " & str2)也可以
    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        Dim z As Integer
        Dim x As String = " 100"
        z = 50
        MessageBox.Show(x & z) ''   MessageBox.Show(x + z)
    End Sub
End Class