物件初始化器

• 命名型別

   Dim someInstance As New SomeClass(argument) With {
       .Member1 = value1,
       .Member2 = value2
       '...
   }
  

  相當於

   Dim someInstance As New SomeClass(argument)
   someInstance.Member1 = value1
   someInstance.Member2 = value2
   '...
  

• 匿名型別 （選項推斷必須開啟）

    Dim anonymousInstance = New With {
        .Member1 = value1,
        .Member2 = value2
        '...
    }
  

  雖然類似的 anonymousInstance 與 someInstance 的型別不同

  成員名稱在匿名型別中必須是唯一的，並且可以從變數或其他物件成員名稱中獲取

    Dim anonymousInstance = New With {
        value1,
        value2,
        foo.value3
        '...
    }
    ' usage : anonymousInstance.value1 or anonymousInstance.value3
  

  每個成員都可以以 Key 關鍵字開頭。那些成員將是 ReadOnly 屬性，那些沒有將是讀/寫屬性

    Dim anonymousInstance = New With {
        Key value1,
        .Member2 = value2,
        Key .Member3 = value3
        '...
    }
  

  使用相同成員定義的兩個匿名例項（名稱，型別，Key 和 order 的存在）將具有相同的匿名型別。

    Dim anon1 = New With { Key .Value = 10 }
    Dim anon2 = New With { Key .Value = 20 }
  
    anon1.GetType Is anon2.GetType ' True
  

  匿名型別在結構上是等同的。具有至少一個具有相同 Key 值的 Key 屬性的相同匿名型別的兩個例項將是相等的。你必須使用 Equals 方法來測試它，使用 = 將無法編譯，Is 將比較物件引用。

    Dim anon1 = New With { Key .Name = "Foo", Key .Age = 10, .Salary = 0 }
    Dim anon2 = New With { Key .Name = "Bar", Key .Age = 20, .Salary = 0 }
    Dim anon3 = New With { Key .Name = "Foo", Key .Age = 10, .Salary = 10000 }
  
    anon1.Equals(anon2) ' False
    anon1.Equals(anon3) ' True although non-Key Salary isn't the same
  

Named 和 Anonymous 型別的初始值設定項都可以巢狀和混合

    Dim anonymousInstance = New With {
        value,
        Key .someInstance = New SomeClass(argument) With {
            .Member1 = value1,
            .Member2 = value2
            '...
        }
        '...
    }