獲取字典值

你可以使用 Item 屬性獲取字典中條目的值：

Dim extensions As New Dictionary(Of String, String) From {
    { "txt", "notepad" },
    { "bmp", "paint" },
    { "doc", "winword" }
}

Dim program As String = extensions.Item("txt") 'will be "notepad"

' alternative syntax as Item is the default property (a.k.a. indexer)
Dim program As String = extensions("txt") 'will be "notepad"

' other alternative syntax using the (rare)
' dictionary member access operator (a.k.a. bang operator)
Dim program As String = extensions!txt 'will be "notepad"

如果字典中不存在該鍵，則將丟擲 KeyNotFoundException。