C# WinForm控件開發設置默認值是非常有必要的，實現起來也很容易，本文筆者為你介紹設置默認值的方法，希望能給你帶來幫助。

　　如果你為屬性設定了默認值，那么當開發者修改了屬性的值，這個值在Property Explorer中將會以粗體顯示。VS為屬性提供一個上下文菜單，允許程序員使用C# WinForm控件開發把值重置為默認值。

　　當Visual Studio進行控件的串行化時，他會判斷那些值不是默認值，只有不是設置默認值的屬性才會被串行化，所以為屬性提供設置默認值時可以大大減少串行化的屬性數目，提高效率。

　　那么Visual Studio進怎么知道我們的屬性值不是默認值了呢？我們需要一種機制來通知Visual Studio進默認值。實現這種機制有兩種方法：

　　對于簡單類型的屬性，比如Int32，Boolean等等這些Primitive類型，你可以在屬性的聲明前設置一個DefaultValueAttribute，在Attribute的構造函數里傳入設置默認值。

　　對于復雜的類型，比如Font，Color，你不能夠直接將這些類型的值傳遞給Attibute的構造函數。相反你應該提供Reset 和ShouldSerialize 方法，比如ResetBackgroundColor(),ShouldSerializeBackgroundColor()。

　　VS能夠根據方法的名稱來識別這種方法，比如Reset  方法把重置為設置默認值，ShouldSerialize 方法檢查屬性是否是設置默認值。過去我們把它稱之為魔術命名法，應該說是一種不好的編程習慣，可是現在微軟依然使用這種機制。我還是以前面幾篇文章使用的例子代碼。

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　　在上面C# WinForm控件開發的代碼中，我增加了兩個屬性，一個是DisplayText，這是一個簡單屬性，我們只需要在它的聲明前添加一個DefaultValue Attribute就可以了。

　　另外一個是TextColor屬性，這個復雜類型的屬性，所以我們提供了ResetTextColor和ShouldSerializeTextColor來實現默認值。

　　C# WinForm控件開發設置默認值的實現就講完了，但是有一點不要忽視了，你已經設置默認值，就應該相應的初始化這些屬性，比如我們例子中的代碼：

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p?r?i?v?a?t?e ?C?o?l?o?r? ?_?t?e?x?t?C?o?l?o?r=C?o?l?o?r?.?R?e?d?;?

　　以上介紹的就是C# WinForm控件開發如何設置屬性的默認值，希望對你有所幫助。