vb.net 语法

IF

If intNumber = 1000 Then
MessageBox.Show("'intNumber' is, indeed, 1000!", "Simple If")
ElseIf intNumber = 27 Then
MessageBox.Show("'intNumber' is 27!", "Simple If")
Else
MessageBox.Show("'intNumber' is not 1000!", "Simple If")
End If
单行的if语句 不需要End If 单行的If语句如果需要执行多个操作, 需要用冒号隔开.
不等于的符号 <> 也可以用 If Not strName = "Wendy" Then

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逻辑操作符写法 And Or
不区分大小写 ToLower toUpper

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Select Case
Select Case strName.ToLower
Case "eddie","ccc","bbb",
strFavoriteColor = "Passionate Purple"
Case "katelyn"
strFavoriteColor = "Red"
Case Else
'do something here
End Select

For...Next

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 循环

循环 可以指定步长 步长可以为负数--从大到小循环
Do Untile 条件 ' 直到所给的条件满足为止
语句....
Loop
与之相对的是 Do While Loop语句
Until 和 While可以放到Loop之后 这样循环至少执行一次
与Do While Loop 对应的老的形式的循环是 While End While
退出循环 用 Exit For 和 Exit Do来退出循环

退出当前循环,执行下一次 Continue For 和 Continue Do

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 定义数组

Dim strArr(9) As String ' 注意,这儿的9 是 last index,也就是说,数组的长度是10

Array.Sort(strArr) ' 可以使用这个方法对数组排序

Reverse方法可以对数组反向

也可以使用下面的方法定义数组并赋值

Dim strArr2 As String = {"a","b","c"}

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 枚举类型定义  enum

常量 const

结构定义 用 structure

list 用 ArrayList

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